ELECTROMAGNETIC FIELDS AND THEIR
EFFECT ON ANIMAL
BEHAVIOR AND ENDOCRINOLOGY; A RESEARCH BIBLIOGRAPHY
When reviewing
the research
bibliography below, keep in mind that the studies use a wide range of
pulsed electromagnetic frequencies.
Therefore,
It is VERY IMPORTANT to differentiate between effects of
frequencies below 15 Hz (low Beta-rhythm
brainwave state = FOCUSED - NO STRESS) and those
above 15 Hz ( mid Beta-Rhythm brainwave state or higher)
resulting in negative
behavioral modification and stress chemical synthesis. You'll see the
pattern form as you read down the page.
Nearly
every therapeutic PEMF system has all or
most programs above the 15 Hz threshold which we feel is a huge
mistake. Although PEMF studies show enhanced rates of healing at a wide
range of frequencies, the
"sweet" spot for physiological healing is 10 Hz, plain and
simple as proven by the Eastern European researchers in the 1970's and
1980's. NASA/Goodwin confirmed in 2003. Further studies on the
mitochondria find beneficial effects at 10 Hz as well while
mitochondria subject to power frequency have less than robust survival
rates when insulted by hypoxic shock (no oxygen). Based upon historical
data, we believe it makes no
sense whatsoever to use higher frequencies for ANY therapeutic purpose
while limiting exposure to higher-frequency
EMF from all sources.
Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino,
Moscow
region, 142290 Russia. tsemenova@venus.iteb.serpukhov.su
The effects of ultra low power pulse-width + modulation electromagnetic
radiation (EMR, power density 10 mc/Wt/cm2, carrying frequency 915 MHz,
modulating pulses with frequency 4, 6, 16 and 20 Hz, duration 10 min)
on the rat
emotional behavior and motor activity in the elevated plus-maze were
studied. It
was established that EMR (frequency of modulation 4 and 6 Hz)
significantly
decreased the emotionally negative reactions of anxiety and fear by a
factor of
3.7 (p < 0.01) and 4.5 (p < 0.01) correspondingly and increased
by a factor of
1.9-2.2 (p < 0.05) exploratory activity. On the contrary EMR
(frequency of
modulation 20 Hz) significantly increased by a factor of (p < 0.05)
emotionally
negative reactions of anxiety and fear and decreased by a factor of 1.8
(p <
0.05) the exploratory activity in rats.
PMID: 11155339 [PubMed - indexed for MEDLINE]
1: Zh Vyssh Nerv Deiat Im I P Pavlova. 2000 Jul-Aug;50(4):703-15.Links
[Species specificity, age factors, and various
neurochemical correlates of the animal spontaneous behavior after
exposure to electromagnetic field of the ultralow intensity]
[Article in Russian]
National Research Center Institute of Medical and
Biological Problems, Moscow, Russia.
Behavioral and neurochemical reactions of small
laboratory animals (mice and rats of different age) under exposure to
ultralow-intensity electromagnetic fields (EMF, frequency of 4200 and
970 MHz, modulated by a quasistochastic signal in the range of
20-20,000 Hz, power density 15 microW/cm2, specific body absorption
rate up to 4.5 mJ/kg) were studied. The EMF basically inhibited the
locomotor and exploratory activity in the "open-field" test. The
species- and age-specific features rather than radiation conditions
dominated. However, decrease in the EMF frequency considerably
intensified the observed effect. Change in animal behavior was
accompanied by shifts in neurochemical processes, i.e., sharp
activation of serotoninergic and inhibition of morepinephrinergic
system.
1: Georgian Med News. 2006 Nov;(140):91-3.Links
[Influence of the chronic exposure to network
frequency electromagnetic field on rats under interrupted and
continuous action of EMF]
[Article in Russian]
Tamasidze A G .
The aim of the study was the investigation of
chronic exposure to network frequency electromagnetic field in the rats
under interrupted or continuous action of electric magnetic field. We
were studying their behavior by the method of "open field". Comparison
of behavior of rats in the "open field" has shown that the significant
difference in the emotional activity of rats was stated. The number of
boluses and urination in rats of B group is 4,5 times more than in the
individuals of C group (p<0,001), but the significant difference
between the rats of control A and B groups has not been stated.
Although, the number of boluses in the rats of B group was a little
raised, this raise was not statistically significant (p<0,5). The
rats of control A and C groups significantly distinguished from one
another. The number of boluses and urination in the animals of C group
was significantly lower (p<0,001). In that way, the rats which were
under the discontinuous action of electromagnetic field were
distinguished by high emotionality, which occur by increase of boluses
and urination, the high number grooming behavior and increase of the
number of translocation, that influences the functioning of
hypothalamohypophysial system.
1: Zh Vyssh Nerv Deiat Im I P Pavlova. 2000 Jul-Aug;50(4):703-15.Links
[Species specificity, age factors, and various
neurochemical correlates of the animal spontaneous behavior after
exposure to electromagnetic field of the ultralow intensity]
[Article in Russian]
National Research Center Institute of Medical and
Biological Problems, Moscow, Russia.
Behavioral and neurochemical reactions of small
laboratory animals (mice and rats of different age) under exposure to
ultralow-intensity electromagnetic fields (EMF, frequency of 4200 and
970 MHz, modulated by a quasistochastic signal in the range of
20-20,000 Hz, power density 15 microW/cm2, specific body absorption
rate up to 4.5 mJ/kg) were studied. The EMF basically inhibited the
locomotor and exploratory activity in the "open-field" test. The
species- and age-specific features rather than radiation conditions
dominated. However, decrease in the EMF frequency considerably
intensified the observed effect. Change in animal behavior was
accompanied by shifts in neurochemical processes, i.e., sharp
activation of serotoninergic and inhibition of morepinephrinergic
system.
1: Georgian Med News. 2006 Nov;(140):91-3.Links
[Influence of the chronic exposure to network
frequency electromagnetic field on rats under interrupted and
continuous action of EMF]
[Article in Russian]
Tamasidze A G .
The aim of the study was the investigation of
chronic exposure to network frequency electromagnetic field in the rats
under interrupted or continuous action of electric magnetic field. We
were studying their behavior by the method of "open field". Comparison
of behavior of rats in the "open field" has shown that the significant
difference in the emotional activity of rats was stated. The number of
boluses and urination in rats of B group is 4,5 times more than in the
individuals of C group (p<0,001), but the significant difference
between the rats of control A and B groups has not been stated.
Although, the number of boluses in the rats of B group was a little
raised, this raise was not statistically significant (p<0,5). The
rats of control A and C groups significantly distinguished from one
another. The number of boluses and urination in the animals of C group
was significantly lower (p<0,001). In that way, the rats which were
under the discontinuous action of electromagnetic field were
distinguished by high emotionality, which occur by increase of boluses
and urination, the high number grooming behavior and increase of the
number of translocation, that influences the functioning of
hypothalamohypophysial system.
[The effect of electromagnetic radiation on the monoamine oxidase A
activity in
the rat brain]
Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino,
Moscow
oblast, Russia. dolgacheva@hotmail.com
The effect of the ultralow power pulse-modulated electromagnetic
radiation (EMR,
power density 10 microW/cm2; carrying frequency 915 MHz; modulating
pulses with
frequency 2, 4, 6, 8, 12, 16 and 20 Hz) on activity of monoamine oxidase
(MAO-A), enzyme involved in the oxidative deamination of monoamines, was
investigated. It was established that the increase of activity MAO in
hypothalamus reached the maximal meaning at modulation frequency of 6
Hz that
corresponded 160% (p < 0.01) of the control level; and at modulation
frequency
of 20 Hz the decrease of enzyme activity up to 74% (p < 0.01) was
found. Mainly
the action of ultralow power pulse-modulated EMR on activity of MAO in
hippocamp
was activating; and the maximal increase of enzyme activity up to 174%
(p <
0.01) was registered at modulation frequency of 4 Hz.
PMID: 11031490 [PubMed - indexed for MEDLINE]
1: Zh Vyssh Nerv Deiat Im I P Pavlova. 2000 Jul-Aug;50(4):703-15.Links
[Species specificity, age factors, and various
neurochemical correlates of the animal spontaneous behavior after
exposure to electromagnetic field of the ultralow intensity]
[Article in Russian]
National Research Center Institute of Medical and
Biological Problems, Moscow, Russia.
Behavioral and neurochemical reactions of small
laboratory animals (mice and rats of different age) under exposure to
ultralow-intensity electromagnetic fields (EMF, frequency of 4200 and
970 MHz, modulated by a quasistochastic signal in the range of
20-20,000 Hz, power density 15 microW/cm2, specific body absorption
rate up to 4.5 mJ/kg) were studied. The EMF basically inhibited the
locomotor and exploratory activity in the "open-field" test. The
species- and age-specific features rather than radiation conditions
dominated. However, decrease in the EMF frequency considerably
intensified the observed effect. Change in animal behavior was
accompanied by shifts in neurochemical processes, i.e., sharp
activation of serotoninergic and inhibition of morepinephrinergic
system.
Action of modulated electromagnetic fields on the emotional component
of the
systems organization of behavioral acts in rats.
Sudakov KV.
P. K. Anokhin Science Research Institute of Normal Physiology, Russian
Academy
of Medical Sciences, Moscow, Russia.
This article reviews experimental data providing evidence on the
effects of
modulated electromagnetic fields of 30-120 V/m with a carrier frequency
of 30
MHz modulated sinusoidally at frequencies of 2-50 Hz on the emotional
responses
accompanying various stages in the systems organization of behavior in
rats. The
blocking effects of fields were demonstrated in self-stimulation models
in
different types of conditioned reflex behavior, as well as during
extinction of
conditioned reflex responses in individual conditions and emotional
intercourse.
It is suggested that modulated electromagnetic fields which have
information
effects on the body act on the information component of behavior, i.e.,
emotion.
PMID: 9850964 [PubMed - indexed for MEDLINE]
4: Zh Vyssh Nerv Deiat Im I P Pavlova. 2001 May-Jun;51(3):373-7.
[Modulation by ultralow intensity electromagnetic fields on
pharmacologic
effects of psychotropic drugs]
National Research Center Institute of Medical and Biological Problems,
Institute
of Higher Nervous Activity and Neurophysiology, Russian Academy of
Sciences,
Research Institute of Psychiatry, Russian Ministry of Public Health,
Moscow.
The ultralow-intensity electromagnetic fields (EMF, frequency of 4200,
modulated
by a quasistochastic signal in the range of 20-20,000 Hz, power density
of 15
microW/cm2, specific body absorption rate up to 4.5 mJ/kg) potentiated
the
hypnogenic effect of hexenal. The exposure to the EMF shortened the
time of
falling asleep induced by this drug and increased sleep duration in
rats. The
exposure to the EMF also potentiated haloperidol catalepsy: it
decreased the
drug threshold dose and increased the catalepsy duration. The EMF
influence on
the haloperidol effects was of a prolonged character: it was manifest
in a
selected suppression of the emotional excitation in the open-field test
within
24 hours after the exposure.
PMID: 11550647 [PubMed - indexed for MEDLINE]
5: Bioelectromagnetics. 1993;14(4):287-97.
Behavioral effects of long-term exposure to magnetic fields in rats.
Trzeciak HI, Grzesik J, Bortel M, Kuska R, Duda D, Michnik J, Malecki A.
Department of Pharmacology, Silesian Academy of Medicine, Katowice,
Poland.
Male rats and pregnant and nonpregnant female rats of the Wistar strain
were
sham-exposed or exposed to static (0.49 T) or to extremely low
frequency (50 Hz)
magnetic fields (0.018 T) 2 h per day for 20 consecutive days. Measures
of
irritability, exploratory activity, and locomotion were made in that
order
before and after the 4th, 10th, and 17th 2-h exposures. A reliable
decrease in
the irritability of rats after repeated exposure to a static or
undulating field
was found. No significant effects of treatment conditions on open-field
behavior
and locomotor activity were observed. Pregnancy had no influence on the
behavioral end points. These results indicate that irritability of rats
may be
used as a simple behavioral indicant of mammalian sensitivity to
magnetic
fields.
PMID: 8216385 [PubMed - indexed for MEDLINE]
6: Zh Vyssh Nerv Deiat Im I P Pavlova. 2000 Sep-Oct;50(5):867-77.
[The neurotropic effects of low-intensity electromagnetic waves in rats
with
different typological characteristics of higher nervous activity]
National Research Center, Institute of Medical and Biological Problems,
Moscow.
The effects of the ultralow-intensity electromagnetic fields (EMF,
frequency of
4200 and 970 MHz, modulated by a quasistochastic signal in the range of
20-20,000 Hz, power density 15 microW/cm2, specific body absorption
rate up to
4.5 mJ/kg) on the reactions of the central nervous system (CNS) of rats
with
different types of behavior were studied. Some neurochemical and
behavioral
mechanisms of rats' reactions were investigated. It was shown that the
EMF
produce pronounced changes in the state and activity of monoaminergic
brain
systems. These changes, on the whole, correspond to the alterations at
the
integrative level (predominantly, of the inhibitory character).
PMID: 11085002 [PubMed - indexed for MEDLINE]
7: Aviakosm Ekolog Med. 1997;31(5):70-5.
[Combined effect of hypokinesia of various duration and gamma-radiation
on
central nervous system activity in rats]
[Article in Russian]
Shtemberg AS.
State Research Center "Institute of Medical Biological Problems", RF.
There studied the effects of a combined effect of hypokinesia (HK) of
various
duration (7 and 30 days, corresponding to the stages of anxiety and
resistance
of general adaptation syndrome) and gamma-radiation dose of 3 Gy on the
formation of differentiated motor-drinking conditioned reflex (CR) in
the rats.
It is demonstrated that the applied exposures lead to the various
disorders of
the higher nervous activity of the test animals: after 7-day
hypokinesia in the
behaviour there prevail the fear and emotional-vegetative components
whereas
following 30-day hypokinetic exposure there occurs some stimulation of
the
orientation-exploratory behaviour with concurrent enhancement of the
inertness
of nervous processes and the tendency to formation of stringent
behavioural
stereotypes slowing-down the conditioned reflex formation. A modifying
effect of
radiation counts only after 30-day hypokinesia and consists in the
development
of extra-limited inhibition (reaction of acquired helplessness) in the
part of
animals.
PMID: 9508401 [PubMed - indexed for MEDLINE]
8: Folia Med (Plovdiv). 1999;41(3):75-80.
Effects of low-intensity electromagnetic fields on behavioral activity
of rats.
Kemerov S, Marinkev M, Getova D.
Department of Physical Medicine and Rehabilitation, Higher Medical
Institute,
Plovdiv, Bulgaria.
The present study aimed at comparative assessment of the changes in
behavioral
activity of rats after exposing them to low intensity electromagnetic
fields
(EMFs) in the meter, decimeter and centimeter ranges. The experiments
were
carried out on 24 Wistar rats divided into 4 groups (1 control and 3
experimental), treated with different EMFs. The rats were irradiated on
the head
area at power density of 10 mW/cm2. Using a conventional shuttle box,
the
conditioned and non-conditioned responses and spontaneous motor
activity of the
rats were studied. The results suggest that exposure to EMFs in the
three ranges
can slow down the formation of conditioned responses--this was clearly
marked in
the rats exposed to meter EMFs, whereas the effects of centimeter EMFs
were
delayed in time. The behavioral effects were mild at athermal dosages
and the
animals adapted easily to exposure conditions. This study shows that
determination of the effects of different EMFs should be done for each
of the
ranges separately; determination of the exact dosage of the
electromagnetic
fields can help to avoid their negative biological effects.
PMID: 10658372 [PubMed - indexed for MEDLINE]
9: Zh Vyssh Nerv Deiat Im I P Pavlova. 2000 Jul-Aug;50(4):703-15.
[Species specificity, age factors, and various neurochemical correlates
of the
animal spontaneous behavior after exposure to electromagnetic field of
the
ultralow intensity]
National Research Center Institute of Medical and Biological Problems,
Moscow,
Russia.
Behavioral and neurochemical reactions of small laboratory animals
(mice and
rats of different age) under exposure to ultralow-intensity
electromagnetic
fields (EMF, frequency of 4200 and 970 MHz, modulated by a
quasistochastic
signal in the range of 20-20,000 Hz, power density 15 microW/cm2,
specific body
absorption rate up to 4.5 mJ/kg) were studied. The EMF basically
inhibited the
locomotor and exploratory activity in the "open-field" test. The
species- and
age-specific features rather than radiation conditions dominated.
However,
decrease in the EMF frequency considerably intensified the observed
effect.
Change in animal behavior was accompanied by shifts in neurochemical
processes,
i.e., sharp activation of serotoninergic and inhibition of
morepinephrinergic
system.
PMID: 10984915 [PubMed - indexed for MEDLINE]
10: Gig Sanit. 1987 Jul;(7):26-9.
[Hygienic evaluation of electromagnetic fields in the 17-cm range based
on
research data on behavioral reactions]
[Article in Russian]
Dumanskii IuD, Zotov SV.
PMID: 3666487 [PubMed - indexed for MEDLINE]
11: Radiobiologiia. 1990 May-Jun;30(3):395-9.
[The effect of an SHF field on the dopamine-dependent behavior of rats]
[Article in Russian]
Andreeva LA, Konovalov VF.
A study was made of the influence of SHF radiation (8 mW/cm2, carrier
frequency
0.88 Hz, modulation frequency 16 Hz) on rotation of rats induced by
apomorphine.
A single exposure within an hour was shown to inhibit
apomorphine-induced
rotation by 21%. Daily one-hour exposure within 5 days caused a more
pronounced
inhibition of test-response. Different individual sensitivity to SHF
radiation
was noted.
PMID: 2371398 [PubMed - indexed for MEDLINE]
12: Bioelectromagnetics. 1999 Sep;20(6):378-86.
Influence of combined DC and AC magnetic fields on rat behavior.
Zhadin MN, Deryugina ON, Pisachenko TM.
Institute of Cell Biophysics, Moscow Region, Russia.
zhadin@online.stack.net
The action of combined parallel static (DC) and alternating (AC)
magnetic fields
at the cyclotron frequencies for different biologically active ions,
specifically, calcium, sodium, potassium, chlorine, magnesium and
lithium, on
rat behavior in the "open field" were investigated. It was shown that
the DC and
AC fields at the calcium cyclotron frequency lower the locomotor and
exploratory
activity of the rats, whereas action of the fields at the magnesium
cyclotron
frequency enhances these forms of behavioral activity. The effects were
qualitatively alike at the weak (50 microT) and relatively strong (500
microT)
DC fields with proportional changes in the frequencies and amplitudes
of the AC
fields. Statistically significant effects of cyclotron frequencies for
other
ions studied were not observed. Copyright 1999 Wiley-Liss, Inc.
[Radiation-induced changes of circadian dynamics in the behavioral
reactions of
rats in the "open field"]
[Article in Russian]
Davydova OE.
The interaction of daily motor activity rythm within daily changes of
early
transient neurological disorders (ENTD) symptoms has been evaluated.
The highest
frequency of five ENTD symptoms was mainly observed in that daily
periods when
behavior reactions were minimal. A difference was distinguished in
circadian
radiosensitivity of some behavior reactions in "open field"
(gamma-irradiation
60Co, 62.5 Gy). The most radiosensitive ENTD symptoms were "vertical
set",
"immobility" and "motion on the spot", characterized emotional state and
orienting-locomotor animal reactions. Certain changes of orto- and
paraphases of
these behavior reactions biorythms due to irradiation have been
revealed.
PMID: 8293103 [PubMed - indexed for MEDLINE]
14: Radiat Res. 1995 Jul;143(1):93-7.
Lack of behavioral effects in non-human primates after exposure to
ultrawideband
electromagnetic radiation in the microwave frequency range.
Sherry CJ, Blick DW, Walters TJ, Brown GC, Murphy MR.
Systems Research Laboratories, Armstrong Laboratory, Brooks Air Force
Base,
Texas 78235, USA.
The effect of acute exposure to ultrawideband (UWB) electromagnetic
radiation on
the Primate Equilibrium Platform (PEP) task, where the monkey's task is
to
manipulate a joystick control to compensate for the random
perturbations in the
pitch plane that are generated by a computer at unpredictable
intervals, was
examined. The duration of the UWB exposure was 2 min at a pulse
repetition rate
of 60 Hz (total of 7200 pulses). The bandwidth of the pulse was 100 MHz
to 1.5
GHz (peak power between 250-500 MHz) with a peak E-field strength of
250 kV/m.
Each monkey was exposed twice. The interval between exposures was 6
days. The
exposure to UWB electromagnetic radiation had no effect on PEP
performance when
tested immediately after exposure.
PMID: 7597150 [PubMed - indexed for MEDLINE]
15: Fiziol Zh Im I M Sechenova. 1995 Apr;81(4):21-31.
[The physiological mechanisms of the regulation of zoosocial behavior
in rats
exposed to low-frequency electromagnetic fields]
[Article in Russian]
Sidiakin VG, Stashkov AM, Ianova NP, Chemodanova MA, Shumilina KA,
Kirillova AV.
The infraslow frequency electromagnetic fields were shown to affect
social
activity in rats: the changes induced by territorial priority and
isolation were
eliminated, an interaction between the motor activity and the social
status
appeared. The monoaminergic system of the rat brain seems to take part
in
physiological mechanisms of regulation of the zoosocial behaviour
according to
changes in ambient conditions.
PMID: 7581573 [PubMed - indexed for MEDLINE]
16: Proc Soc Exp Biol Med. 1995 Nov;210(2):171-9.
Effects of prenatal ultrasound exposure on adult offspring behavior in
the
Wistar rat.
Jefferson Medical College, Thomas Jefferson University, Philadelphia,
Pennsylvania 19107, USA.
An ultrasound exposure tank was specifically designed for experimental
bioeffects studies. Thirty-six pregnant rats were anesthetized,
immersed to the
axilla in a water tank, and exposed on Day 15, 17, and 19 of gestation.
Twelve
rats were exposed to 5.0 MHz pulsed ultrasound of effective pulse
duration equal
to approximately 0.170 microseconds, pulse repetition rate (PRF) 1 kHz,
and a
spatial peak, temporal peak intensity (lsptp) of 500 W/cm2,
representing a
clinically appropriate exposure level. The spatial peak pulse average
(lsppa),
spatial peak temporal average (lspta), and instantaneous maximum (lm)
intensities were determined to be 100 W/cm2, 24 mW/cm2, and 230 W/cm2,
respectively. The maximum rarefraction pressure, pr, was measured as
12.5 x
10(5) Pa, and the total power was 2.5 mW. Twelve other rats were
exposed to 1500
W/cm2, lsptp, and 12 were sham insonified. Since the focal area was
about 0.05
cm2, computer controlled stepper motors moved the rats through the
ultrasound
field to ensure uniform exposure of the abdominal/pelvic region. Total
exposure
time was 35 min. A miniature thermocouple was implanted in a few rats
to verify
that no significant temperature increase took place due to exposure. A
total of
278 offspring were maintained until postnatal Day 60 when they were
subjected to
two of four behavioral tests in random order within sexes. The results
indicate
no consistently observed dose-related alterations in adult behavior due
to
prenatal fetal exposure to 5.0 MHz ultrasound below an intensity
(lsptp) of 1500
W/cm2.
PMID: 7568288 [PubMed - indexed for MEDLINE]
17: Biofizika. 2002 Jan-Feb;47(1):71-7.
[Suppression of nonspecific resistance of the body under the effect of
extremely
high frequency electromagnetic radiation of low intensity]
[Article in Russian]
Kolomytseva MP, Gapeev AB, Sadovnikov VB, Chemeris NK.
Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino,
Moscow
Region, 142290 Russia.
The dynamics of leukocyte number and functional activity of peripheral
blood
neutrophils under whole-body exposure of healthy mice to low-intensity
extremely-high-frequency electromagnetic radiation (EHF EMR, 42.0 GHz,
0.15
mW/cm2, 20 min daily) was studied. It was shown that the phagocytic
activity of
peripheral blood neutrophils was suppressed by about 50% (p < 0.01
as compared
with the sham-exposed control) in 2-3 h after the single exposure to
EHF EMR.
The effect persisted for 1 day after the exposure, and then the
phagocytic
activity of neutrophils returned to the norm within 3 days. A
significant
modification of the leukocyte blood profile in mice exposed to EHF EMR
for 5
days was observed after the cessation of exposures: the number of
leukocytes
increased by 44% (p < 0.05 as compared with sham-exposed animals),
mostly due to
an increase in the lymphocyte content. The supposition was made that
EHF EMR
effects can be mediated via the metabolic systems of arachidonic acid
and the
stimulation of adenylate cyclase activity, with subsequent increase in
the
intracellular cAMP level. The results indicated that the whole-body
exposure of
healthy mice to low-intensity EHF EMR has a profound effect on the
indices of
nonspecific immunity.
PMID: 11855293 [PubMed - indexed for MEDLINE]
18: Vrach Delo. 1991 Mar;(3):49-51.
[The biological activity of a decameter-range electromagnetic field
with a
frequency of 24 MHz]
[Article in Russian]
Bezdol'naia IS, Dumanskii IuD, Smolia AL.
A study of behavioural reactions indicates that the effect of 24 MHz
frequencies
of the electromagnetic field results in changes of the ratio of
excitatory and
inhibitory processes in the nervous system of white rats with
prevalence of
inhibitory processes. By the 90-th day of effect of the above factor
all changes
returned to the initial level. This indicates stability of the
adaptative
reactions of the integrative level of the nervous system to the acting
factor.
PMID: 2042349 [PubMed - indexed for MEDLINE]
19: Gig Sanit. 1991 May;(5):28-30.
[Late sequelae of the effect of electromagnetic field on animals]
[Article in Russian]
Gromyko NM, Krivodaeva OL, Zemskova VV.
Simple and complex forms of behaviour, gas composition and
acid-alkaline blood
status in rats following exposure to the electro-static field (ESF) and
iraionization, as well as in their offspring were studied. It has been
found
out, that ESF combined with the negative polarity air ionization damage
motor
and sex activity, conditioned-reflectory activity, changes blood
indices. The
observed disturbances in the organism of parent animals influenced fetus
development.
PMID: 1916334 [PubMed - indexed for MEDLINE]
20: Ukr Biokhim Zh. 1979 Jan-Feb;51(1):14-7.
[Effect of high frequency electromagnetic fields on the processes of
transamination in the liver and small intestine tissues of rats]
[Article in Russian]
Faitel-berg-Blank VR, Lekhan IG.
The influence of electromagnetic waves of metrical and centimetrical
range on
the transaminoferases activity was studied in the liver and small
intestine of
69 rats. The experiment shows that the activity of aspartate and alanine
aminotransferases is dependent on the power and duration of the action.
It is
established that the action of both the short-wave 160 mA diathermy and
30
MW/cm2 microwaves for 20 min is accompanied by inhibition of the liver
and small
intestine aminotransferases activity. The 20 min action of 12 MW/cm2
microwaves
induces an increase in the aminotransferases activity of the liver,
small
intestine and serum.
Factor analysis shows that female rat behaviour is characterized
primarily by
activity, male rats are driven by sex and anxiety.
Fernandes C, Gonzalez MI, Wilson CA, File SE.
Psychopharmacology Research Unit, Neuroscience Research Centre, GKT
School of
Biomedical Sciences, King's College London, Guy's Campus, UK.
This experiment explored sex differences in behaviour using factor
analysis to
describe the relationship between different behavioral variables. A
principal
component solution with an orthogonal rotation of the factor matrix was
used,
ensuring that the extracted factors are independent of one another, and
thus
reflect separate processes. In the elevated plus-maze test of anxiety,
in male
rats factor 1 accounted for 75% of the variance and reflected anxiety,
factor 2
represented activity, and accounted for 24% of the variance. This
contrasted
with the finding in female rats in which factor 1 was activity,
accounting for
57% of the variance, with the anxiety factor accounting for only 34% of
the
variance. When behaviour in both the plus-maze and holeboard were
analysed, a
similar sex difference was found with anxiety emerging as factor 1 in
males and
holeboard activity as factor 1 in females. Locomotor activity in the
inner
portion of the holeboard loaded on the anxiety factor for males, but on
activity
for females. When behaviours in the plus-maze and sexual orientation
tests were
analysed, anxiety emerged as factor 1 in males, sexual preferences
factor 2, and
activity factor 3. In females, activity was factor 1, sexual preference
factor
2, anxiety factor 3, and social interest factor 4. These results
suggest caution
should be exercised in interpreting the results from female rats in
tests
validated on males because the primary controlling factor may be
different.
PMID: 10593196 [PubMed - indexed for MEDLINE]
22: Ross Fiziol Zh Im I M Sechenova. 1997 Sep;83(9):12-21.
[The action of a modulated electromagnetic field on the emotional
component of
the systemic organization of behavioral acts in rats]
[Article in Russian]
Sudakov KV.
Anokhin Institute of Normal Physiology, Russian Acad. Med. Sci.,
Moscow, Russia.
Experimental findings are reviewed in respect to the effect of modulated
electromagnetic field (MEMF) upon emotional responses of rats
accompanying
various phases of systemic organisation of their behaviour. Blocking
effects of
the MEMF are shown in simulated self-stimulation and various
conditioned types
of behaviour in rats. In author's opinion, the MEMF affect the
informative
component of behaviour: emotions.
Medical Radiological Research Centre, Russian Academy of Medical
Sciences,
Obninsk, 249036 Russia.
Research has been carried out to investigate the effects of microwave
exposure
(7 GHz, surface energy density 10-50 mW/cm2, SAR 2.1-10.5 W/kg) on
learned
behaviors of rats in the paradigm of conditioned avoidance reflex. It
was shown
that transitory reductions in conditioned behavior after acute microwave
exposure occurred at an SAR equal to the intensity of rat basal
metabolism. It
was found cumulative effects for intermittent exposures of rats at a
power
density of 10 mW/cm2.
[Effect of low intensity pulse-modulated electromagnetic radiation on
activity
of alkaline phosphatase in blood serum]
[Article in Russian]
Pashovkina MS, Akoev IG.
Institute of Cell Biophysics, Russian Academy of Sciences, 142292
Pushchino,
Moscow Region, 142292 Russia. Pashamar@rambler.ru
The change in alkaline phosphotase activity in vitro with frequencies
modulation
at low intensity of pulse-modulated electromagnetic radiation was
experimentally
shown (EMR, 2375 MHz, intensity: 0.8, 8.0; 40.0 microW/cm2; range
modulation:
30-310 Hz; time of interaction: 1-3 min). Revealed effects could be
regarded as
an evidence of informative character of interaction of modulated EMR.
PMID: 11253703 [PubMed - indexed for MEDLINE]
25: Brain Res Bull. 2002 Jan 1;57(1):17-26.
Learned fear, emotional reactivity and fear of heights: a factor
analytic map
from a large F(2) intercross of Roman rat strains.
Aguilar R, Gil L, Flint J, Gray JA, Dawson GR, Driscoll P,
Gimenez-Llort L,
Escorihuela RM, Fernandez-Teruel A, Tobena A.
Medical Psychology Unit, Department of Psychiatry and Forensic
Medicine, School
of Medicine, Autonomous University of Barcelona, Barcelona, Spain.
raul.aguilar@uab.es
Anxiety-related behaviours were evaluated across various tests in a 800
F(2)-intercross of the Roman high- and low-avoidance inbred rats. These
tests
either evoke unlearned (open field [OF]; plus-maze [PM]; hole-board
[HB];
spontaneous activity [A]; and acoustic startle reflex [ASR]) or learned
(classical fear conditioning [CFC]; and shuttlebox avoidance
conditioning
[SAC]), anxious/fearful responses. Using factor analysis (oblique
rotation), we
obtained a six-fold solution with 14 variables derived from all tests.
These six
factors represented SAC, CFC, PM anxiety, PM and OF activity, ASR
anxiety, plus
a mixed whole of anxious and activity variables (from OF and A),
respectively.
In searching for a smaller number of meaningful factors, we applied a
three-factor solution that coherently corresponded with differentiated
facets of
fearfulness, rather than with the tests. Results showed that (1)
measures of SAC
and CFC strongly loaded onto Factor 1, labelled as "Learned Fear"; (2)
a blend
of almost all variables loaded onto Factor 2, called "Emotional
Reactivity"; and
(3) open arm behaviour in the PM loaded onto Factor 3, called "Fear of
Heights."
After discussing limitations of this apparently consistent behavioural
map of
anxiety, we advance some connections between those factors with
quantitative
trait loci candidates (genetic markers) as detected in the same sample.
PMID: 11827733 [PubMed - indexed for MEDLINE]
26: Zhonghua Yu Fang Yi Xue Za Zhi. 1995 Jan;29(1):41-3.
[Effects of pregnant exposure to electromagnetic field emitted by
electric
blankets on brain catecholamine and behavior in offspring mice]
[Article in Chinese]
Yao G, Fu Y, Lu D.
Microwave Laboratory, Zhejiang Medical University, Hangzhou.
NIH pregnant mice were exposed to electromagnetic field emitted by
electric
blankets with 1-1.2kV/m and 0.2-0.4microT for five hours daily during
their
whole gestational period. Catecholamine (CA) content in the
hypothalamus of
their newborn offsprings was quantitatively measured with histochemical
methods,
and their varied behavioral activities were determined with behavioral
toxicological methods. Results showed catecholamine content in exposed
offsprings decreased significantly not only seven days but also 40 days
after
delivery as compared with the controls (P < 0.01 and P < 0.05,
respectively).
[Dependence of microwave effect on the secondary structure of DNA on
molecular
weight of polynucleotide]
[Article in Russian]
Semin IuA, Shvartsburg LK, Zhavoronkov LP.
Medical Radiological Research Centre, Russian Academy of Medical
Science,
Obninsk, 249036 Russia.
The effect of ultralow power pulse-modulated electromagnetic radiation
(average
power density 60 microW/cm2, carrying frequency 1.05; 2.12; or 2.39 GHz;
modulating pulses with frequency 4 Hz) on the secondary structure of
DNA was
investigated. It was established that the exposure of beta-alanine and
formaldehyde containing aqueous DNA solution to electromagnetic
radiation had
activated the process of DNA despiralization under the action of
beta-alanine--formaldehyde reaction product. The effect of
electromagnetic
radiation on the secondary structure of DNA can be removed by lowering
of
molecular weight of DNA to 0.46 x 10(6) (at carrying frequency 1.05
GHz), or to
0.25 x 10(3) (at carrying frequency 2.39 GHz).
Institute of Medical-Biological Problems, State Scientific Center of
the Russian
Federation, Moscow.
The effects of low-intensity electromagnetic waves (4200 MHz, modulated
with
quasichaotic signals at 20-20,000 Hz, energy density 15 microW/cm2;
specific
energy absorption not greater than 15 mJ/kg) on the neurochemical
systems of the
brain and on behavioral reactions were studied in experimental animals
with
different typological characteristics of higher nervous activity. These
studies
showed that electromagnetic waves produced marked changes in the state
and
activity of the monoaminergic mediator systems which were in general
terms
concordant with changes at the integrative level (mostly selective
inhibitory
effects). The nature of these processes depended to a significant
extent on the
typological characteristics of the animals.
PMID: 11693480 [PubMed - indexed for MEDLINE]
29: Mutat Res. 1998 Apr;410(2):185-220.
Animal and cellular studies on carcinogenic effects of low frequency
(50/60-Hz)
magnetic fields.
Loscher W, Liburdy RP.
Department of Pharmacology, Toxicology and Pharmacy, School of
Veterinary
Medicine, Hannover, Germany.
[Effect of a hypogeomagnetic field on warm-blooded animals]
[Article in Russian]
Levina RV, Smirnov RV, Olimpienko TS.
This paper presents the study of the effect of a 3-month exposure of
adult male
rats of the Wistar strain to the hypogeomagnetic field (the shielding
factor =
172.5) on their behavior, learning ability, cardiovascular function and
work
capacity. It was found that the exposure led to a significant decrease
of work
capacity, endurance and behavioral activity as well as to a significant
increase
of heart rate and time of conditioned reflex development. The above
changes
remained within physiological limits due to which they can be viewed as
adaptation variations.
PMID: 2709751 [PubMed - indexed for MEDLINE]
31: Life Sci. 2003 Apr 18;72(22):2489-98.
Combined effects of complex magnetic fields and agmatine for contextual
fear
learning deficits in rats.
Acute post-training exposures to weak intensity theta-burst stimulation
(TBS)
patterned complex magnetic fields attenuated the magnitude of
conditioned fear
learning for contextual stimuli. A similar learning impairment was
evoked in a
linear and dose-dependent manner by pre-conditioning injections of the
polyamine
agmatine. The present study examined the hypothesis that whole-body
applications
of the TBS complex magnetic field pattern when co-administered with
systemic
agmatine treatment may combine to evoke impairments in contextual fear
learning.
Within minutes of 4 mg/kg agmatine injections, male Wistar rats were
fear
conditioned to contextual stimuli and immediately exposed for 30 min to
the TBS
patterned complex magnetic field or to sham conditions. TBS patterned
complex
magnetic field treatment was found to linearly summate with the
contextual fear
learning impairment evoked by agmatine treatment alone. Furthermore, we
report
for sham-treated rats, but not rats exposed to the synthetic magnetic
field
pattern, that the magnitude of learned fear decreased and the amount of
variability in learning increased, as the K-index (a measure of change
in
intensity of the time-varying ambient geomagnetic field) increased
during the
3-hr intervals over which conditioning and testing sessions were
conducted.
PMID: 12650857 [PubMed - indexed for MEDLINE]
32: Behav Pharmacol. 1999 Mar;10(2):131-7.
Effects of GABA-transporter (GAT) inhibitors on rat behaviour in
open-field and
elevated plus-maze.
Schmitt U, Hiemke C.
Department of Psychiatry, University of Mainz, Germany.
The behavioural consequences of inhibition of gamma-aminobutyric acid
(GABA)
uptake were studied. Two GABA uptake inhibitors, tiagabine and SKF
89976-A, were
administered to rats, and behaviour was analysed 30 min later in a
standard open
field, an enriched open field, and an elevated plus-maze. Eight groups
of
animals received either saline (0.9%), tiagabine, or SKF 89976-A. At a
dose of
18.5 mg/kg, tiagabine, an established antiseizure drug, impaired motor
coordination, enhanced exploratory activity and reduced anxiety related
behaviour. SKF 89976-A exhibited minimal effects over the dose range
tested.
These results indicate that inhibition of GABA uptake might be a
pharmacological
strategy to treat not only epilepsy, but also anxiety disorders.
[Effect of low-intensity electromagnetic fields of industrial frequency
on the
ultrastructure and proliferative activity of rat's thymus cells]
[Article in Russian]
Zhitkevich TI, Bokut' TB, Netukova NI.
Institute of Physiology, National Academy of Sciences, Minsk, 220072
Belarus.
biblio@fizio.bas-net.by
Effects of two types of low-intensity electromagnetic fields (EMF) of
industrial
frequency (50 Hz) on the fine structure and proliferative activity of
thymic
cells in white rats were studied. It was found that a weak EMF with a
prevailing
electrical component (380-480 V/m, 120-140 nT1) did not affect the DNA
synthesis
intensity. An EMF with a stronger magnetic induction (10-15 V/m,
800-1500 nT1)
diminished the glucose-6-phosphate dehydrogenase activity and
proliferative
processes in cultured stimulated lymphocytes. Electron microscopic
investigation
of the thymus after both types of exposure revealed an accumulation of
lymphocytes with pyknotic nuclei and electron-dense cytoplasm, as well
as
hypoplasia of the vascular endothelium. At the same time, EMF with a
prevailing
magnetic component produced a more marked negative effect on the
ultrastructure
of thymic cells, which indicated a lowered secretory activity of
epitheliocytes.
PMID: 11605242 [PubMed - indexed for MEDLINE]
34: Behav Brain Res. 2002 Jul 18;133(2):323-32.
Emotional changes related to age in rats--a behavioral analysis.
Boguszewski P, Zagrodzka J.
Department of Neurophysiology, Nencki Institute of Experimental
Biology, 3
Pasteur St., 02-093, Warsaw, Poland.
The present study investigated age-related differences in the emotional
behavior
of rats using factor analysis to identify motivational factors
influencing
spontaneous behavior in open field with illuminated center (OF), plus
maze (EPM)
and social interactions test. Animals of the same strain, bred under
the same
conditions, formed two experimental groups: young adults (YA, N=20)
tested at
the age of 4 months and old rats (OA, N=16) tested at the age of 24
months. The
computer video based tracking system EthoVision was used for automated
acquisition and analysis of data. The results of each test were analyzed
separately for YA and OA by factor analysis. Two main independent
factors
emerged from the analysis of OF measures-factor 1, which appeared to
reflect
motor activity, and factor 2, reflecting anxiety. The measures best
reflecting
motor activity (distance moved in the peripheral zone) and anxiety
(time spent
in central zone) decreased significantly with age. Factor analysis for
EPM
measures revealed, in both groups, three independent factors. In YA,
factor 1
reflected motor activity, factor 2-anxiety, in OA measures of anxiety
loaded on
factor 1, measures of activity on factor 2. Factor 3 in both groups
appeared to
represent a decision making process. The number of entries to the
closed arms
declined significantly in OA, showing an age related decrease of motor
activity.
Also, the ratio of open arms entries in relation to the total number of
entries
decreased in OA, indicating a higher anxiety level. Three independent
factors
emerged from the analysis of social interaction measures. The pattern
of factor
loading was different in young and old animals, although the number and
time of
social interactions did not show age-related differences. In addition
to a
decrease of motor activity we conclude that old rats also differ from
young
animals in emotional and social behavior.
PMID: 12110466 [PubMed - indexed for MEDLINE]
35: Aviat Space Environ Med. 1995 Jun;66(6):562-7.
No detectable bioeffects following acute exposure to high peak power
ultra-wide
band electromagnetic radiation in rats.
Systems Research Laboratories, Inc., Brooks AFB, TX 78235, USA.
A wide range assessment of the possible bioeffects of an acute exposure
to high
peak power ultra-wide band (UWB) electromagnetic radiation was
performed in
rats. The UWB-exposure consisted of 2 min of pulsed (frequency: 60 Hz,
pulse
width: 5-10 ns) UWB (bandwidth: 0.25-2.50 GHz) electromagnetic
radiation. Rats
were examined using one of the following: 1) a functional observational
battery
(FOB); 2) a swimming performance test; 3) a complete panel of blood
chemistries;
or 4) determination of the expression of the c-fos protein in
immunohistologically-stained sections of the brain. No significant
differences
were found between UWB- or sham-exposed rats on any of the measured
parameters.
PMID: 7646407 [PubMed - indexed for MEDLINE]
36: Lab Anim. 1995 Oct;29(4):380-4.
Effects of gentling on open-field behaviour of Wistar rats in
fear-evoking test
situation.
Hirsjarvi P, Valiaho T.
University of Kuopio, Department of Applied Zoology, Finland.
The effect of individual gentling on open-field behaviour of adult male
Wistar
rats was studied. Dark open-field evoked prey-like behaviour both in
the gentled
and in the nonhandled rats. Escape activity dominated in both groups
although
some habituation as a function of trials occurred. The effects of
gentling were
mainly seen in the quality of the fear-reaction as a result of reduced
fear of
human contact. Parameters that differentiated the 2 groups were middle
field
ambulation, middle field rearing and passive motionlessness.
PMID: 8558819 [PubMed - indexed for MEDLINE]
37: Am Ind Hyg Assoc J. 1993 Apr;54(4):186-96.
Biological effects of extremely low-frequency electromagnetic fields:
in vivo
studies.
Anderson LE.
Bioelectromagnetics, Battelle, Pacific Northwest Laboratory, Richland,
WA 99352.
This paper discusses the biological effects of exposure to extremely low
frequency electromagnetic fields observed in animal studies. Three
areas of
investigation are reported: (1) studies on the nervous system, including
behavior and neuroendocrine function; (2) experiments on cancer
development in
animals; and (3) measurements of currents and electric fields induced
in animal
models by exposure to external magnetic fields. An attempt is made to
evaluate
experimental results and interpret them with respect to potential health
implications.
Publication Types:
Review
Review, Tutorial
PMID: 8480634 [PubMed - indexed for MEDLINE]
38: Sci Total Environ. 1996 Feb 2;180(1):35-42.
Experimental study of the effects of radiofrequency electromagnetic
fields on
animals with soft tissue wounds.
Detlavs I, Dombrovska L, Turauska A, Shkirmante B, Slutskii L.
Latvian Medical Academy, National Hospital of Traumatology and
Orthopaedics,
Riga.
The effect of radio frequency electromagnetic fields (RF EMF) was
studied on
Wistar rats with excised full-thickness dermal wounds in the
interscapular
region. The wounded regions of experimental animals were subjected to
EMF for 30
min daily during the first 5 days after wound infliction. Control
animals
received no treatment. We used RF EMF with (1) frequency 53.53 GHz
without
modulation; (2) frequency 42.19 GHz without modulation; (3) frequency
42.19 GHz,
but with a frequency modulation band 200-MHz wide. On the 7th day the
animals
were terminated and the granulation-fibrous tissue (GFT) developed in
the wounds
was subjected to complex quantitative biochemical analysis. RF EMF
without
frequency modulation decreased the amounts of glycoprotein
macromolecules,
diminishing the inflammatory exudation. In striking contrast, under the
influence of RF EMF with frequency modulation, hexoses and especially
sialic
acid concentrations were significantly elevated (P < 0.001). This
indicated
intensification of exudative phenomena. As a consequence of inflammation
inhibition in the treatment without frequency modulation, the total
collagen
accumulation was lowered. However, when frequency was modulated, the
inflammatory phenomena were intensified, and pronounced accumulation of
collagenous proteins was noted. Thus, our experiments confirm the
effects of
non-thermal EMF on the reparative-proliferative processes of animals
with soft
tissue wounds.
PMID: 8717318 [PubMed - indexed for MEDLINE]
39: Behav Neurosci. 2001 Apr;115(2):429-36.
Dimensions of emotionality in a rat model of innate anxiety.
Ohl F, Toschi N, Wigger A, Henniger MS, Landgraf R.
Behavioral Neuroendocrinology, Max Planck Institute of Psychiatry,
Munich,
Germany. ohl@mpipsykl.mpg.de
Emotionality is thought to be multidimensional, with "anxiety"
representing one
dimension. Dissecting emotional dimensions in animal models is an
essential
prerequisite for investigating the neurobiological mechanisms that
underlie
anxiety. The authors used factor analysis to investigate emotional
dimensions in
normal rats and rats bred for either high or low anxiety-related
behavior.
Hyperanxious rats were reduced in emotional dimensions in the elevated
plus-maze
by selection pressure, and a modified hole board test revealed a
dissection of
their emotionality with precisely defined dimensions. This enabled clear
differentiation of "anxiety" from other emotional dimensions including
risk
assessment behavior and exploration. Factors extracted by analyzing
data from a
multiple-test battery corresponded to particular test characteristics
rather
than to emotional dimensions. The approach used might help to develop
specific
treatment strategies for anxiety disorders.
PMID: 11345967 [PubMed - indexed for MEDLINE]
40: Indian J Biochem Biophys. 1999 Oct;36(5):348-51.
Effects of extremely low frequency electromagnetic fields on health.
Jain SC, Tyagi K.
Centre for Environment & Explosive Safety, Metcalfe House, Delhi.
This paper gives a brief review of the physical interaction and
bio-effects of
exposure to extremely low frequency (ELF) electromagnetic fields (EMF)
along
with guidelines on limits of exposure to 50/60 Hz electric and magnetic
fields.
Publication Types:
Review
Review, Tutorial
PMID: 10844987 [PubMed - indexed for MEDLINE]
41: Environ Health Perspect. 1979 Jun;30:115-21.
Study of nonionizing microwave radiation effects upon the central
nervous system
and behavior reactions.
Shandala MG, Dumanskii UD, Rudnev MI, Ershova LK, Los IP.
The biologic effect of an electromagnetic field of a frequency of 2375
+/- 50
MHz was studied in rats and rabbits in specially constructed absorbant
chambers.
The results of the investigations have shown that microwave radiation
of 10, 50,
500 mu W/cm2 for 30 days, 7 hr/day, causes a number of changes in
bioelectric
brain activity and also in behavioral immunological, and cytochemical
reactions.
It was found that levels of 10 and 50 mu W/cm2 stimulate the electric
brain
activity at the initial stage of irradiation, while a level of 500 mu
W/cm2
causes its suppression, as seen from the increase of slow, high
amplitude
delta-waves. At 500 mu W/cm2 a decrease in capacity of work, in value of
unconditioned feeding stimulus, in investigating activity, electronic
irradiation threshold, and in inhibition of cellular and humoral
immunity were
also observed.
PMID: 446442 [PubMed - indexed for MEDLINE]
42: Zh Vyssh Nerv Deiat Im I P Pavlova. 2000 Sep-Oct;50(5):878-83.
[The dynamics of the manifestation of behavioral audiogenic seizure
activity in
rats under the action of a modulated and a nonmodulated electromagnetic
field]
[Article in Russian]
Konovalov VF, Serikov IS.
Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino.
It was shown that the electromagnetic field of low intensity modifies
the evoked
epileptiform seizure activity in rats. Cumulative effect of the
electromagnetic
field persisted over the course of 6 months. It was suggested that
inhibition of
the increased motor activity under exposure to electromagnetic field is
caused
by the involvement of dopaminergic brain systems and development of the
resonance effects in cortico-subcortical brain structures under the
influence of
modulated electromagnetic fields.
PMID: 11085003 [PubMed - indexed for MEDLINE]
43: Lik Sprava. 1995 Jul-Aug;(7-8):37-9.
[The cytogenetic action of electromagnetic fields in the short-wave
range]
[Article in Russian]
Timchenko OI, Ianchevskaia NV.
Electromagnetic field (EMF) at a frequency of 24 or 14 MEGC and
intensity of 400
or 200 V/m, increases numbers of hepatocytes from rats with chromosomal
aberrations 1.4-1.5-fold. The magnitude of the response does not appear
to
change with the increase in the field intensity EMF at the above
frequencies and
intensity of 100 V/m does not cause any cytogenetic effects. No such
effects
were notable with EMF-frequency of 4 MEGC.
PMID: 8846369 [PubMed - indexed for MEDLINE]
44: IEEE Eng Med Biol Mag. 2002 Jan-Feb;21(1):90-1.
EMF cancer scares: epidemiology versus body power.
Deutsch S.
deutsch@eng.usf.edu
PMID: 11935994 [PubMed - indexed for MEDLINE]
45: Fiziol Zh Im I M Sechenova. 1994 Jun;80(6):50-62.
[Intersystemic functional integration under the action on the body of
electromagnetic factors]
[Article in Russian]
Vediaev FP, Samokhvalov VG.
Frequency zones of the brain electrical activity, heart rate and
respiration
were studied through certain parameters characterised by individual
asymmetry
and low but stable intersystemic integration. Chronic electromagnetic
irradiation reduced a resistance against an emotional stress as
manifested in a
"decay" of individual spatial-temporal infrastructure of informational
parameters of the EEG, heart rate and respiration.
PMID: 7531066 [PubMed - indexed for MEDLINE]
46: Peptides. 2001 Jul;22(7):1031-6.
Comparison of neurokinin SP with diazepam in effects on memory and fear
parameters in the elevated T-maze free exploration paradigm.
Echeverry MB, Hasenohrl RU, Huston JP, Tomaz C.
Laboratory of Psychobiology, University of Sao Paulo, Ribeirao Preto,
Brazil.
The elevated T-maze was combined with a free exploration protocol,
which, in
contrast to the conventional procedure, dispenses with handling of the
animals
during the experimental sessions. This allows measurement of fear
indexes
derived from the elevated plus-maze as well as assessment of
acquisition of open
arm avoidance and open arm escape in one continuous session. Retention
of the
different fear-responses is measured 72 h later without drug treatment.
In order
to assess the effects of two known anxiolytics in this paradigm, rats
received
an IP injection of diazepam (1 to 4 mg/kg), substance P (5 to 500
microg/kg) or
vehicle (1 ml/kg) and were tested on the T-maze for 5 min. Diazepam
elevated
open arm activity, indicative of an anxiolytic effect. The drug also
increased
the latency to escape from the open arms, but did not significantly
affect
acquisition of open arm avoidance. During the retention trial, diazepam
in
higher doses impaired the performance of both fear-responses,
suggestive of an
anterograde amnesic effect. Substance P did not influence acquisition
and
retention of open arm avoidance and escape. However, in high doses, the
peptide
increased the sojourn time in the central arena of the maze, indicating
reduced
fear and, hence, a dissociation between anxiolytic and amnesic effects.
The
present findings demonstrate that the elevated T-maze free exploration
paradigm
is sensitive to anxiolytic and memory-modulating effects of drugs.
[A comparative histochemical study of cytochrome oxidase activity in the
somatosensory and auditory brain centers in the normal rat and after
exposure to
superhigh-frequency electromagnetic fields]
[Article in Russian]
Krasnoshchekova EI, Rumiantseva TA, Kulikov GA.
Using histochemical method mitochondrial cytochrome oxydase (CO) in
acoustic and
somatosensory centers of rat brain has been studied to reveal CO
activity
distribution in norm and after impulse-modulated high-ultra-high
frequency
influence. After ultra-high frequency influence the increase of enzymic
activity
in a number of regions of rat brain centers with relationship to
processing
ecologically important sensory signals is revealed.
Anxiogenic-like effect of serotonin(1B) receptor stimulation in the rat
elevated
plus-maze.
Lin D, Parsons LH.
Department of Neuropharmacology, CVN-7, Division of Psychopharmacology,
The
Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA
92037,
USA. lparsons@scripps.edu
Perturbations in serotonin [5-hydroxytryptamine (5-HT)]
neurotransmission have
been implicated in several psychiatric illnesses including depression
and
anxiety disorders. It is not yet clear, however, which of the 14
currently
identified 5-HT receptor subtypes in the brain participate in the
regulation of
emotional states. This study investigates a role for the 5-HT(1B)
receptor
subtype in anxiety-related behaviors using the elevated plus-maze
paradigm in
rats. The selective 5-HT(1B) receptor agonist
3-(1,2,5,6-tetrahydro-4-pyridyl)-5-propoxypyrrolo[3,2-b]pyridine (CP
94,253;
1--5.6 mg/kg) dose-dependently decreased the amount of exploration on
the open
arms of the plus-maze without altering overall locomotor activity. This
5-HT(1B)
agonist-induced increase in anxiety-like behavior was dose-dependently
reversed
by coadministration of the selective 5-HT(1B/1D) receptor antagonist
2'-methyl-4'-(5-methyl[1,2,4]oxadiazol-3-yl)-biphenyl]-amide (GR
127,935). There
was no significant effect of GR 127,935 administration alone on
plus-maze
behavior. These results indicate that 5-HT(1B) receptor activation
increases
anxiety-like behavioral responses as measured by the elevated
plus-maze. Since
5-HT(1B) receptors modulate the activity of multiple neurotransmitter
systems
that have been implicated in anxiety disorders, these findings suggest
that this
receptor subtype may represent an important therapeutic target for the
treatment
of anxiety.
PMID: 11888549 [PubMed - indexed for MEDLINE]
49: Phytomedicine. 2000 Jun;7(3):199-203.
Agastache mexicana may produce anxiogenic-like actions in the male rat.
Molina-Hernandez M, Tellez-Alcantara P, Martinez E.
Instituto de Investigaciones Psicologicas, Universidad Veracruzana,
Mexico.
mimoli@bugs.invest.uv.mx
Behavioral effects of a water-soluble extract of Agastache mexicana, a
plant
with purported anxiolytic actions, were studied in male Wistar rats. In
the
elevated plus-maze test, various doses of the plant extract (3.0 mg/kg
body wt.;
9.0 mg/kg body wt.; 12.0 mg/kg body wt.) administered intraperitoneally
(i.p.)
decreased the exploration of open arms, showing an anxiogenic-like
effect.
Agastache mexicana (12 mg/kg body wt.; i.p.) did not change immobility
in the
forced swimming test (i.e., had no anti-depressant effect) but
increased the
anti-immobility action of 32.0 mg/kg body wt. (i.p.) of desipramine
(i.e.,
increased the antidepressant-like effect of desipramine). A. mexicana
had no
effect on exploratory activity in an open field test, indicating that
it had no
sedative effect at the doses used. It is concluded that effects of the
water
extract of A. mexicana are more consistent with an anxiogenic-like
property than
an anxiolytic-like one.
[Changes in the proteinase-inhibitor system of rats with
hyperlipoproteinemia
during transcerebral exposures to a 100-Hz-frequency pulse current and
to an
ultrahigh-frequency field]
Experiments on 36 male rats with experimental hyperlipoproteinemia
demonstrated
that transcerebral exposure to impulse current (100 Hz, 2mA) aggravates
atherogenic alterations, provokes hyperactivation of kallikrein-kinin
system and
unbalance of elastase inhibitory activity in the serum and myocardium.
The
latter may contribute to better vascular permeability for low-density
lipoproteins, to development of edema of vascular intima, lability of
cellular
and lysosomal membranes with hydrolysis of elastine and collagen fibers
of
myocardial vessels and other organs. Transcerebral exposure to
electromagnetic
UHF field (40.68 MHz) is not hypolipidemic but has no negative effect on
experimental atherosclerosis, promotes normalization of
kallikrein-kinin system
in the serum, activation of this system in the myocardium and cerebral
cortex,
correction of destructive processes in the serum and cerebral cortex
with a risk
of their development in the myocardium.
PMID: 10429563 [PubMed - indexed for MEDLINE]
51: J Comp Physiol Psychol. 1975 Apr;89(2):183-8.
Avoidance by rats of illumination with low power nonionizing
electromagnetic
energy.
Frey AH, Feld SR.
Rats spent more time in the halves of shuttle boxes that were shielded
from
illumination by 1.2 GHz microwave energy than in the unshielded. In
Experiment
1, rats avoided the energy when it was presented as 30-musec pulses
with a pulse
repetition rate of 100 pulses per second (pps). The average power
density was
about .6 mW/cm2, and the peak power density was about 200 mW/cm2. In
Experiment
2, the energy was presented both continuously and in pulse-modulated
form, i.e.,
.5-msec exponentially decaying pulses at a rate of 1,000 pps. The
average power
density of the continuous energy was 2.4 mW/cm2, and the average power
density
of the pulse-modulated energy was .2 mW/cm2. The peak power density of
the
modulated energy was 2.1 mW/cm2. The rats avoided the pulsed energy,
but not the
continuous energy.
PMID: 1133237 [PubMed - indexed for MEDLINE]
52: Biull Eksp Biol Med. 1977 Aug;84(8):146-9.
[Hypnogenic action of a modulated electromagnetic field]
[Article in Russian]
Sudakov KV, Antimonii GD.
Behavioristic and electroencephalographic changes in rats under
long-lasting
modulated electromagnetic field (frequency of 40 MHz, modulation
frequency 50
Hz, intensity 100--120 V/m) were studied. Some phasic disorders in the
conditioned feeding and defense reactions were observed, including
cataleptic
state as a result of the action of modulated electromagnetic field.
These
behavioristic disorders are determined by the changes in the normal
cortico-subcortical relationships.
PMID: 561631 [PubMed - indexed for MEDLINE]
53: Bull Exp Biol Med. 2000 Aug;130(8):746-8.
Emotional state and one-trial learning in OXYS rats with hereditarily
elevated
production of oxygen radicals.
Loskutova LV, Kolosova NG.
Institute of Physiology, Siberian Division of the Russian Academy of
Medical
Sciences, Novosibirsk.
Comparative analysis of unconditioned and conditioned behavior of
Wistar and
prematurely aging OXYS rats revealed that the latter have significantly
reduced
locomotor and exploratory activities, increased anxiety in the elevated
plus-maze test, spatial disorientation, and abnormal associative
learning. OXYS
rats can be used as a biological model for studying molecular,
neurobiological,
and neurochemical mechanisms of brain aging.
PMID: 11177232 [PubMed - indexed for MEDLINE]
54: Z Naturforsch [C]. 1994 May-Jun;49(5-6):352-8.
Resonance effect of low-intensity millimeter waves on the chromatin
conformational state of rat thymocytes.
Belyaev SYa, Kravchenko VG.
Scientific Research Center Vidguk, Moscow Engineering Physics
Institute, Russia.
The method of anomalous viscosity time dependencies (AVTD) was modified
for the
study of the changes in the chromatin conformational state (CCS) of rat
thymocytes of the Wistar line. The response of the thymocytes of male
rats to
low-intensity millimeter waves (MMW) was examined. It was shown that
MMW at
power densities (PD) of 1 microW/cm2 produced a resonance effect on the
CCS in
the frequency range of 41.56-41.67 GHz. The resonance frequency of the
cell
response did not vary significantly among five examined rats and was
determined
to be 41.61 +/- 0.01 GHz. A halfwidth of resonances was averaged to 40
MHz. The
power dependence of the resonance effect was measured in the range of
10(-11)-10(-4) W/cm2. Statistically significant changes in CCS were
registered,
starting with 10(-9) W/cm2. Right- and left-handed circularly polarized
MMW were
shown to differ in efficiency at the resonance frequency. The
established
regularities in the thymocyte response to low-intensity MMW was very
similar to
those which have been previously found for E. coli cells.
[Effect of low-frequency pulse-modulated 460 MHz electromagnetic
irradiation on
Drosophila embryos]
[Article in Russian]
Bol'shakov MA, Kniazeva IR, Lindt TA, Evdokimov EV.
Tomsk State University, 634050 Russia. physiol@bio.tsu.ru
Effect of electromagnetic radiation 460 MHz with 2.5-40 Hz pulse
modulation rate
on Drosophila embryos of 15 h 10 m age was studied. It was demonstrated
that a
5-min irradiation with 0.12 W/kg average SAR (3 W/kg pulsed SAR) alters
the
Drosophila percentage of interrupted development. The effect strength
depended
on the modulation rate with a pronounced decrease at 10 and 16 Hz. A
hypothesis
about the presence of thermal and non-thermal mechanisms of action of
pulse-modulated microwave radiation diversely effecting the embryos has
been put
forward and grounded.
PMID: 11605241 [PubMed - indexed for MEDLINE]
56: Zh Vyssh Nerv Deiat Im I P Pavlova. 1993 Mar-Apr;43(2):398-406.
[The effect of different motor regimens modulating spontaneous activity
on rat
behavior]
[Article in Russian]
Kulikov VP, Kiselev VI, Konev IV.
A method was developed of non-stressful modulation of spontaneous motor
activity
of rats. Restraint of mobility was found to inhibit spontaneous
activity.
Physiological stimulation of muscle activity by means of complication of
food-procuring behaviour was accompanied by increase of spontaneous
activity.
Physiological stimulation of motor activity was characterized by
stability of
orienting-exploratory behaviour, emotional reactivity, expression of
"freedom
response", the best learning and working abilities of the animals.
Regimes with
imposing or restriction of muscle activity favoured the inhibition of
spontaneous activity and the decrease of efficiency of adaptive
behaviour. Motor
regimes accompanied by increase of spontaneous activity were found to
be optimal
for adaptive behaviour.
[The delayed effects of modulated and non-modulated electromagnetic
field on
epileptiformic activity in rats]
[Article in Russian]
Konovalov VF, Serikov IS.
Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino,
142290
Russia.
The modifying influence of the weak electromagnetic field on the
development of
the audiogenic spasmodic activity in rats was shown. The decrease of
lifetime of
experimental rats exposed to electromagnetic fields with different
parameters
and development of tumours (in one set of experiments) was found.
PMID: 11402555 [PubMed - indexed for MEDLINE]
58: Acta Med Austriaca. 2000;27(3):69-77.
[Electromagnetic fields--effects on health]
[Article in German]
Stepansky R, Jahn O, Windischbauer G, Zeitlhofer J.
Universitatsklinik fur Neurologie, Wien.
This literature review shows the current knowledge of health effects on
humans
concerning static, low frequency electric and magnetic fields and high
frequency
electromagnetic fields up to 300 GHz. Basic physical knowledge and the
current
thresholds are demonstrated. Different frequency ranges of
electromagnetic
fields, their natural and technical origins and the different biological
effects, especially possible hazards such as cancerogenity or risks for
the
brain, are discussed. Open questions and future research aspects are
demonstrated. Finally electrosensibility and psychological aspects are
shown.
Publication Types:
Review
Review, Tutorial
PMID: 10897385 [PubMed - indexed for MEDLINE]
59: Life Sci. 2002 Mar 1;70(15):1751-62.
Validation of a behavioral recording automated system in the elevated
plus-maze
test.
Torres C, Escarabajal MD.
Departamento de Psicologia, Facultad de Humanidades y Ciencias de la
Educacion,
Universidad de Jaen, Spain. mctorres@ujaen.es
The elevated plus-maze test has been widely used for screening of
anxiolytic
drugs and for exploring neurobiological bases of anxiety. In this
study, we
validated a new automated system that enables to record exploratory
behavior in
the elevated plus-maze test. This system, called cyberplus, consisted
of ten
pairs of photoelectric cells strategically located in several parts of
the
apparatus, and seemed to be sensitive to the position of the animal's
forepaws,
so it would yield scores in anxiety measurements and locomotor activity
similar
to those obtained by following the traditional procedure, that is, by
analyzing
videotapes by experienced observers. In order to assess this
hypothesis, we
exposed rats to the elevated plus-maze test and compared the scores
obtained by
cyberplus with the values recorded by two independent observers,
conducting a
correlational study with both kinds of recording procedures. The results
obtained suggest the utility of cyberplus as a behavioral recording
automated
system in the elevated plus-maze test, making data collection and data
analysis
easier in exploring pharmacological and neurobiological bases of
anxiety.
Publication Types:
Validation Studies
PMID: 12002520 [PubMed - indexed for MEDLINE]
60: Zh Vyssh Nerv Deiat Im I P Pavlova. 2002 Nov-Dec;52(6):743-9.
[Behavioral consequences of isolation in early ontogeny in rats:
selectivity of
anxiety conditions]
[Article in Russian]
Khonicheva NM, Czabak-Garbacz R, Krupina NA.
Institute of Higher Nervous Activity and Neurophysiology, Russian
Academy of
Sciences, Moscow.
Multiparameter scale for evaluation of anxiety-phobic state in rats
reveals
significant enhancement of anxiety in rat pups after 6-week isolation
(beginning
from the 21st day from birth) as compared to grouped controls of the
same
litter: the locomotion and exploration that appear in test areas are
suppressed,
and species-specific fear reactions are enhanced. These changes
considered as
signs of situational anxiety are not eliminated by 2.5-month keeping in
groups.
Nevertheless, they are not correlated with parameters of the acoustic
startle
reflex that (by the data of literature) is thought to be related with
fear and
anxiety. On the basis of the discrepancy it is proposed that state of
anxiety is
selective. This suggestion is confirmed by individual behavioral
variations
characterized by a combination of a low level of situational anxiety
and a high
level of acoustic anxiety observed in both experimental and control
groups.
These variations may explain the existence of atypical "emotional
resonance"-like behavior according to P.V. Simonov. Attention is given
to
selectively enhanced acoustic startle reflex in the group of active
control as
an evidence for critical importance of any manipulations with social
context in
early ontogeny.
Lack of consistent behavioural effects of Maudsley reactive and
non-reactive
rats in a number of animal tests of anxiety and activity.
Paterson A, Whiting PJ, Gray JA, Flint J, Dawson GR.
Merck Sharp and Dohme Research Laboratories, Neuroscience Research
Centre,
Terlings Park, Eastwick Road, Harlow, Essex CM20 2QR, UK.
RATIONALE: A number of previous studies have reported that the Maudsley
reactive
(MR/Har) and non-reactive (MNRA/Har) strains of rats show behavioural
and
physiological differences consistent with the hypothesis that these
strains
differ in emotionality and could therefore be considered a model of
trait
anxiety in humans. OBJECTIVES: We sought to confirm this observation by
determining their behaviour in various animal models of conditioned and
unconditioned fear. METHODS: Both strains were evaluated in the open
field (OF),
conditioned avoidance (CA), elevated plus maze (EPM) and
fear-potentiated
startle (FPS) tests. In the OF the behaviour of both strains was
consistent with
previous results showing that reactive rats had significantly higher
levels of
defecation and lower levels of activity than the non-reactive rats.
However,
there were no significant strain differences in CA responses or in the
time
spent on the open arms of the EPM. In addition, the full benzodiazepine
receptor
agonist, chlordiazepoxide, induced quantitatively similar effects in
both
strains of rats. In the FPS test, MNRA/Hars had a higher baseline level
of
startle and fear potentiation than the MR/Har rats. CONCLUSIONS: These
data show
that the behaviour of MR/Har and MNRA/Har rats in some models of
conditioned and
unconditioned fear is inconsistent with that predicted by their
behaviour in the
OF test, suggesting that they are not a model of trait fear.
PMID: 11349385 [PubMed - indexed for MEDLINE]
62: Zh Vyssh Nerv Deiat Im I P Pavlova. 1999 Nov-Dec;49(6):1039-45.
[The effect of different stages of the sex cycle on rat behavior in a
plus maze]
[Article in Russian]
Vinogradova EP.
Department of Higher Nervous Activity and Psychophysiology,
St.-Petersburg State
University.
Anxiety and motor activity of female white rats in the elevated
plus-maze were
studied at different stages of the reproduction cycle (estrus, diestrus,
pregnancy and lactation). The level of anxiety was lower, and that of
locomotor
and exploratory activity was higher during estrus and lactation than
during
diestrus and pregnancy. Exposure to chronic pain of threshold intensity
did not
induce behavioral changes in pregnant rats. There was no difference
between the
control and experimental animals in the level of plasma corticosterone.
Motor activity of rabbits under daily thirty-minute irradiation (1.5
GHz, pulse
duration 16 ms, pulse recurrence frequency 0.12 Hz, pulse intensity 0.3
mw/cm2)
for one month was studied. From 14th day the reliable disadaptation
changes such
as an anxiety and alarm reaction were found. The importance of prolonged
irradiation is noted.
PMID: 7719427 [PubMed - indexed for MEDLINE]
64: Bioelectromagnetics. 2000 Oct;21(7):524-37.
Neural and behavioral teratological evaluation of rats exposed to
ultra-wideband
electromagnetic fields.
Cobb BL, Jauchem JR, Mason PA, Dooley MP, Miller SA, Ziriax JM, Murphy
MR.
Air Force Research Laboratory, Human Effectiveness Directorate,
Directed Energy
Bioeffects Division, Radio Frequency Radiation Branch, Brooks AFB, Texas
78235-5324, USA. Brenda.Cobb@AFRLARS.Brooks.af.mil
Several investigators have reported teratologic effects of
electromagnetic field
exposure. The majority of these studies have been performed at levels of
exposure that could produce substantial heating of the animals. New and
unique
sources of ultra-wideband (UWB) electromagnetic fields are currently
being
developed and tested that are capable of generating nonthermalizing,
high-peak-power, microwave (MW) pulses with nanosecond (ns) pulse
widths,
picosecond (ps) rise times, and an UWB of frequencies. Our study was
performed
to determine if teratological changes occur in rat pups as a result of
(i) daily
UWB exposures during gestation days 3-18, or (ii) as a result of both
prenatal
and postnatal (10 days) exposures. Dams were exposed either to (i) UWB
irradiation from a Kentech system that emitted a 55 kV/m-peak E field,
300 ps
rise time, and a 1.8 ns pulse width, average whole-body specific
absorption rate
45 mW/kg; (ii) sham irradiation; or (iii) a positive control, lead (Pb)
acetate
solution (2000 microg/ml) continuously available in the drinking water.
Offspring were examined for ontogeny (litter size, sex-ratios, weights,
coat
appearance, tooth-eruption, eye-opening, air-righting, and ultrasonic
stress
vocalizations). Male pups were tested on various performance measures
(locomotor, water-maze learning, and fertilization capabilities). The
pups
postnatally exposed were examined for hippocampal morphology and operant
behavior. Behavioral, functional, and morphological effects of UWB
exposure were
unremarkable with these exceptions: (i) The UWB-exposed pups emitted
significantly more stress vocalizations than the sham-exposed pups;
(ii) the
medial-to-lateral length of the hippocampus was significantly longer in
the
UWB-exposed pups than in the sham-exposed animals; (iii) male offspring
exposed
in utero to UWB mated significantly less frequently than sham-exposed
males, but
when they did mate there was no difference in fertilization and
offspring
numbers from the sham group. There does not appear to be a unifying
physiological or behavioral relationship among the significant
differences
observed, and our findings could be due to the expected spurious
results derived
when a large number of statistical comparisons are made. Significant
effects
found between our positive-controls and other groups on numerous
measures
indicates that the techniques used were sensitive enough to detect
teratological
effects. Bioelectromagnetics 21:524-537, 2000. Published 2000
Wiley-Liss, Inc.
PMID: 11015117 [PubMed - indexed for MEDLINE]
65: Radiat Res. 2001 Feb;155(2):369-77.
Repeated exposure of C3H/HeJ mice to ultra-wideband electromagnetic
pulses: lack
of effects on mammary tumors.
Air Force Research Laboratory, Radio Frequency Radiation Branch,
Directed Energy
Bioeffects Division, Human Effectiveness Directorate, Brooks Air Force
Base,
Texas, USA.
It has been suggested that chronic, low-level exposure to
radiofrequency (RF)
radiation may promote the formation of tumors. Previous studies,
however, showed
that low-level, long-term exposure of mammary tumor-prone mice to 435
MHz or
2450 MHz RF radiation did not affect the incidence of mammary tumors.
In this
study, we investigated the effects of exposure to a unique type of
electromagnetic energy: pulses composed of an ultra-wideband (UWB) of
frequencies, including those in the RF range. One hundred C3H/HeJ mice
were
exposed to UWB pulses (rise time 176 ps, fall time 3.5 ns, pulse width
1.9 ns,
peak E-field 40 kV/m, repetition rate 1 kHz). Each animal was exposed
for 2 min
once a week for 12 weeks. One hundred mice were used as sham controls.
There
were no significant differences between groups with respect to
incidence of
palpated mammary tumors, latency to tumor onset, rate of tumor growth,
or animal
survival. Histopathological evaluations revealed no significant
differences
between the two groups in numbers of neoplasms in all tissues studied
(lymphoreticular tissue, thymus, respiratory, digestive and urinary
tracts,
reproductive, mammary and endocrine systems, and skin). Our major
finding was
the lack of effects of UWB-pulse exposure on promotion of mammary
tumors in a
well-established animal model of mammary cancer.
PMID: 11175673 [PubMed - indexed for MEDLINE]
66: Ross Fiziol Zh Im I M Sechenova. 2001 Oct;87(10):1450-6.
[Interleukin-1beta and depressive states]
[Article in Russian]
Zubareva OE, Efremov OM, Simbirtsev AS, Klimenko VM.
Institute of Experimental Medicine, Russian Acad. Med. Sci., St.
Petersburg,
197376, Acad. Pavlov St., 12, Russia.
Administration of Interleukin-1 beta (IL-1 beta) in pyrogenic and
subpyrogenic
doses induced a depression of social and exploratory behaviour in rats.
A
reduction in locomotor activity only occurred with pyrogenic doses of
the IL-1
beta. The low dose induced the reduction whereas the high dose the
increase of
anxiety in elevated plus maze. The opposite effects of two doses of
IL-1 beta
were observed also in a test with saccharine.
PMID: 11767459 [PubMed - indexed for MEDLINE]
67: Pol J Occup Med. 1988;1(4):329-39.
Influence of a static magnetic field on the reproductive function,
certain
biochemical indices and behaviour of rats.
Grzesik J, Bortel M, Duda D, Kuska R, Ludyga K, Michnik J, Smolka B,
Sowa B,
Trzeciak H, Zielinski G.
PMID: 2979568 [PubMed - indexed for MEDLINE]
68: Gig Sanit. 1989 Oct;(10):30-2.
[Hygienic evaluation and the problems of standardization of magnetic
fields with
the frequency of 50 Hz]
[Article in Russian]
Ziubanova LF, Karamyshev VB, Shestakov VG.
It is established that some kinds of technological equipment are the
sources of
the magnetic fields with the frequency of 50 Hz, their biologic
activity being
identified. Hygienic classification and approaches to differentiated
standardization of the above factor are suggested with account of time
and
energetic parameters.
PMID: 2599398 [PubMed - indexed for MEDLINE]
69: Ross Fiziol Zh Im I M Sechenova. 2000 Sep;86(9):1167-74.
[Effect of immunization to cholecystokinin fragment (30-33) on the
behavior of
albino rats]
Active immunisation of albino rats by the BSA-conjugated CCK-4 induced
formation
of antibodies to the CCK-4 and some long-term changes of the rat
behaviour.
These changes were contrary to anxiogenic effect of the CCK-4 and
demonstrated
an anxiolytic effect of the immunisation. The data obtained suggest a
possibility of an immunocorrection of pathological anxiety and fear by
an
inverse immunoregulation.
PMID: 11081222 [PubMed - indexed for MEDLINE]
70: Zh Vyssh Nerv Deiat Im I P Pavlova. 1976 Sep-Oct;26(5):899-909.
[Modulated electromagnetic field as a factor of selective influence on
animal
mechanisms of goal-directed behavior]
[Article in Russian]
Sudakov KV.
Proceeding from P.K. Anokhin's theory of the functional systems, the
paper
considers the action of a modulated electromagnetic field (MEMF) on
different
stages of the central architectonics of purposeful behaviour of rats:
afferent
synthesis, decisions making, acceptor of the action results. The action
of MEMF
was studied in different experimental situations: choice of an
alimentary or
defensive reaction to one conditioned stimulus in different situations;
extinction of conditioned alimentary reactions; elaboration and
extinction of
alimentary conditioned reactions in animals group contacts; choice of
the side
of reinforcement in a T-shaped maze, and, lastly, self-stimulation
reactions.
The experiments have shown that MEMF has a selective effect on the
animals'
emotional reactions. Greater disturbances are observed in the
mechanisms of the
animals' appraisal of the action of situational and trigger stimuli or
surrounding individuals of their species and, hence, of decisions
making and
anticipation of future results of the action, the acceptor of the action
results.
PMID: 997935 [PubMed - indexed for MEDLINE]
71: Med Pr. 1981;32(6):393-402.
[Glycosaminoglycans in the brain of rats subjected to electromagnetic
field
action]
[Article in Polish]
Matych S.
Investigations on changes of glucosaminoglycans content were carried
out in the
brain of the rats irradiated once (30 min.) or several times (2-6 hours
daily).
The following frequencies of e-m fields were used: 2880 MHz (pulse
modulation
1000 Hz, pulse duration 1,5 mus); 150 MHz (50 V/m); 175 MHz (150 V/m);
3000 MHz
c.w. continuous wave). Control groups of animals were not subject to
irradiation. Statistically significant increase of GAG content was
found in the
brain of the rats, irradiated in e-m field of frequency 2880 MHz in
comparison
with GAG concentration in the controls. In the brains of animals
exposed to e-m
fields of frequencies 150 and 175 MHz a statistically significant
decrease of
GAG content was noted in comparison with GAG content in the controls.
Whereas
e-m field of frequency 3000 MHz c.w. did not induce statistically
significant
changes in GAG content in experimental animals as compared with the
controls.
PMID: 6804742 [PubMed - indexed for MEDLINE]
72: Biofizika. 2002 Jul-Aug;47(4):759-68.
[A study of absorption of energy of the extremely high frequency
electromagnetic
radiation in the rat skin by various dosimetric methods and approaches]
[Article in Russian]
Gapeev AB, Sokolov PA, Chemeris NK.
Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino,
Moscow
Region, 142290 Russia.
Using experimental and theoretical methods of dosimetry, the energy
absorption
of extremely high-frequency electromagnetic radiation (EHF EMR) in the
skin of
laboratory rats was analyzed. Specific absorption rate (SAR) in the
skin was
determined on the basis of both microthermometric measurements of
initial rates
of temperature rise in rat skin induced by the exposure and
microcalorimetric
measurements of specific heat of the skin. Theoretical calculations of
SAR in
the skin were performed with consideration for dielectric parameters of
rat skin
obtained from the measurements of the standing wave ratio upon
reflection of
electromagnetic waves from the skin surface and for the effective area
of
stationary overheating measured by infrared thermography. A numerical
method was
developed to determine electromagnetic wave energy reflected, absorbed,
and
transmitted in the model of flat layers. The algorithm of the method was
realized in a computer program and used to calculate SAR in the skin on
the
basis of the complex dielectric constant of rat skin. The SAR values
obtained
from experimental measurements, theoretical calculations and numerical
analysis
are in good mutual correspondence and make about 220-280 W/kg at a
frequency of
42.25 GHz and a power of 20 mW at the radiator output. The results
obtained can
be used for dosimetric supply of biomedical experiments on studying the
physicochemical mechanisms of the biological effects of EHF EMR.
PMID: 12298218 [PubMed - indexed for MEDLINE]
73: Gig Sanit. 1991 Aug;(8):52-3.
[Behavioral effects of the combined chronic action of 9375 and 1765 MHz
microwaves]
[Article in Russian]
Navakatikian MA, Nikitina NG, Zotov SV.
Combined pulse-discrete microwave irradiation (9375 and 1765 MHz,
irradiance
flux density to 375 microW/cm2, by 12 h/day for 4 months) caused faint
inhibition of CNS in locomotion activity and defensive reflex
parameters.
[Effects of low-intensity electromagnetic radiation of extremely high
frequency
on the animal body within the framework of total low-dose x-ray
irradiation]
[Article in Russian]
Gubkina EA, Kushnir AE, Bereziuk SK, Potapov VA, Lepekhin EA.
Effect of low-intensive electromagnetic radiation of extremely high
frequency
(EMR EHF) on the rats, subjected to the low-dose X-ray irradiation
(6.192 mC/rg)
was investigated. Content of glial fibrillary acidic protein as well as
glucose
content and activity of glutamate dehydrogenase and malate
dehydrogenase was
studied. It was shown than EMR EHF modifies the X-ray irradiation
effect:
filament GFAP concentration in brain and glucose content in serum were
restored.
The authors suggest central nervous system participation in realization
of EMR
EHF effects on the organism.
PMID: 9019284 [PubMed - indexed for MEDLINE]
75: Radiobiologiia. 1987 Jul-Aug;27(4):567-9.
[Effect of electromagnetic fields of UHF range on dopamine-dependent
behavior of
rabbits]
[Article in Russian]
Andreeva LA, Konovalov VF, Podol'skii IIa.
SHF radiation of low intensity does not influence on a stereotyped
behaviour of
rabbits induced by a dopamine receptor stimulator, apomorphine.
However, 10% of
animals exhibited a marked decrease in the test-response after
SHF-irradiation
(16 Hz) which was perhaps associated with the increased individual
sensitivity
of some animals to SHF-radiation.
PMID: 3628743 [PubMed - indexed for MEDLINE]
76: Zh Vyssh Nerv Deiat Im I P Pavlova. 1998 Nov-Dec;48(6):1043-50.
[The characteristics of the effect of tuftsin on the behavior and on
the level
of biogenic amines in the brain of rats with differing resistance to
acoustic
stress]
[Article in Russian]
Ismailova KhIu, Semenova TP, Iskanderova MD, Fast AE.
Karaev Institute of Physiology, Azerbaijani Academy of Sciences, Baku.
The influence of tetrapeptide tuftsin (Tyr-Lys-Pro-Arg) on learning,
exploratory
activity, emotional behavior, and hypothalamic monoamine content was
studied in
Wistar rats with different resistance to stress induced by acoustic
stimuli.
Positive effects of taftsin were more pronounced in low-resistant rats.
Administration of taftsin induced in these animals a significant
increase in
reactivity to stimuli of different modalities, the open-field
exploratory
activity, rate of alimentary conditioning and its modification in
emotionally
negative situation. Biochemical examinations showed that in rats with
high
resistance to stress taftsin administration led to a decrease in
hypothalamic
noradrenaline level and increase in dopamine and serotonin levels. On
the
contrary, in low-resistant animals taftsin increased the level of
noradrenaline
and decreased that of dopamine, serotonin, and 5-hydroxyindoleacetic
acid. It is
suggested that different behavioral effects of taftsin in
stress-resistant and
nonresistant rats are caused by its different influence on hypothalamic
biogenic
amines.
PMID: 9929913 [PubMed - indexed for MEDLINE]
77: Biofizika. 2000 Jan-Feb;45(1):130-6.
[Changes in serum alkaline phosphatase activity during in vitro
exposure to
amplitude-modulated electromagnetic field of ultrahigh frequency (2375
MHz) in
guinea pigs]
[Article in Russian]
Pashovkina MS, Akoev IG.
Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino,
Moscow
Region, Russia.
The activity of alkaline phosphatase by the action of pulse-modulated
microwave
radiation was studied. The carrier frequency of radiation was 2375 MHz,
the
range of modulation pulse rate was 10-390 Hz with the on-off time ratio
2, and
the specific absorption rate was 8 and 0.8 microW/cm2. Time of exposure
was 1
and 3 min under conditions of continuous temperature control. It was
shown that
the activity of alkaline phosphatase depends on both modulation
frequency and
intensity of superhigh-frequency electromagnetic radiation. At a
frequency of 70
Hz, the activity of alkaline phosphatases increased 1.8-2.0 times.
PMID: 10732222 [PubMed - indexed for MEDLINE]
78: Gig Sanit. 1983 Mar;(3):86-9.
[Age-related sensitivity of the body of an animal to superhigh-frequency
electromagnetic fields]
Power frequency fields promote cell differentiation coincident with an
increase
in transforming growth factor-beta(1) expression.
Aaron RK, Ciombor DM, Keeping H, Wang S, Capuano A, Polk C.
Department of Orthopaedics, Brown University School of Medicine
Providence,
Rhode Island 02906, USA.
Recent information from several laboratories suggest that power
frequency fields
may stimulate cell differentiation in a number of model systems. In
this way,
they may be similar to pulsed electromagnetic fields, which have been
used
therapeutically. However, the effects of power frequency fields on
phenotypic or
genotypic expression have not been explained. This study describes the
ability
of power frequency fields to accelerate cell differentiation in vivo and
describes dose relationships in terms of both amplitude and exposure
duration.
No change in proliferation or cell content were observed. A clear dose
relationship, in terms of both amplitude and duration of exposure, was
determined with the maximal biological response occurring at 0.1 mT and
7-9
h/day. Because this study was designed to explore biological activity at
environmental exposure levels, this exposure range does not necessarily
define
optimal dosing conditions from the therapeutic point of view. This
study reports
the stimulation by power frequency fields of transforming growth
factor-beta, an
important signalling cytokine known to regulate cell differentiation.
The
hypothesis is raised that the stimulation of regulatory cytokines by
electromagnetic fields may be an intermediary mechanism by which these
fields
have their biological activity.
PMID: 10495311 [PubMed - indexed for MEDLINE]
80: Aviat Space Environ Med. 1976 Jun;47(6):644-8.
Effect of electromagnetic pulse on avoidance behavior and
electroencephalogram
of a rhesus monkey.
Mattsson JL, Oliva SA.
A 12-kg male rhesus monkey was exposed to electromagnetic pulse (EMP)
at 266
kv/m, 5 pulses/s, for 1 h (18,700 pulses). The effects of EMP on Sidman
avoidance behavior and on post-exposure electroencephalogram were
evaluated, and
no significant changes were detected. An analysis of an EMP showed that
it
contained various frequency components extending from 0 Hz to 10(9) Hz.
However,
the pulse configuration was such that its power was mainly confined to
the
longer wave-lengths (less than 30 MHz). The lack of biologic effect was
attributed to the fact that the wavelengths were long relative to the
size of
the monkey, and little energy deposition was likely to occur. In
addition, the
electric field was evenly distributed across all lower frequencies so
that only
a very small electric field component existed at any specific low
frequency.
PMID: 820328 [PubMed - indexed for MEDLINE]
81: Bioelectromagnetics. 1989;10(1):111-3.
Intensity threshold for 60-Hz magnetically induced behavioral changes
in rats.
Liboff AR, Thomas JR, Schrot J.
Department of Physics, Oakland University, Rochester, Michigan
48309-4401.
Experiments were conducted to further investigate the effect of 60-Hz
cyclotron-resonance exposures on rats performing on a multiple FR-DRL
schedule.
The previously reported temporary loss of DRL baseline response, when
measured
as a function of A.C. magnetic intensity, was found to have a threshold.
Utilizing the component of A.C. magnetic intensity parallel to the D.C.
field,
we report this threshold as (0.27 +/- 0.10) x 10(-4) Trms.
PMID: 2712836 [PubMed - indexed for MEDLINE]
82: Ross Fiziol Zh Im I M Sechenova. 1998 Oct;84(10):1100-7.
[Anxiety-inducing and -inhibiting agents: differential effect of
pentagastrins
on the white rat behavior]
Parenteral administration of des-BOC-Pentagastrin induced the anxiety
and fear
manifestations, depressing also explorative behaviour in open field
experiments
in rats. Intranasal administration evoked similar effects, whereas
pentagastrin
reduced the anxiety level, increasing explorative behaviour.
Pentagastrin and
des-BOC-Pentagastrin displayed antagonism at the receptor level.
PMID: 10097277 [PubMed - indexed for MEDLINE]
83: Biull Eksp Biol Med. 1991 Feb;111(2):165-8.
[Changes in the emotionally conditioned behavior of rats under the
influence of
the hexapeptide fragment GLLDLK of the protein inhibitor of diazepam
binding]
[Article in Russian]
Zhdanova IV, Kordzadze RN, Pliashkevich IuG.
It is shown that suboccipital injection of 100 micrograms of the
gexapeptide
GLLDLK (the fragment of endogenous peptide--the inhibitor of diazepam
binding)
modified (for 1-3 days) the emotionally conditioned behaviour of the
rats (the
test of "emotional resonance"). This modification was realized in some
reinforcement of different behavioural patterns and had signs of
anxiety and
depression. In the test "social hierarchy" the injection of GLLDLK
didn't change
significantly the hierarchy in the whole rat society, but in the
recipient
behaviour the exploratory activity has been changed, the time of
grooming
increased and the quantity of social contacts decreased.
PMID: 1854959 [PubMed - indexed for MEDLINE]
84: Physiol Behav. 2001 Feb;72(3):403-7.
Exposure to a novel stimulus reduces anxiety level in adult and aging
rats.
Darwish M, Koranyi L, Nyakas C, Almeida OF.
Department of Clinical and Experimental Laboratory Medicine, Faculty of
Health
Sciences, Semmelweis University, Szabolcs u. 33-35, H-1135 Budapest,
Hungary.
Male Wistar rats aged 3, 15 and 24 months were isolated and housed
individually
for 72 h prior to being subjected to inanimate objects (two objects per
rat,
each 1.5 cm in diameter and 4 cm in length, made of surgical gauze).
Following
the exposure to the objects, rats were subsequently tested in an
elevated
plus-maze. The inanimate objects induced locomotor activity, chewing and
transportation of the object. This changed to social interaction and
play-like
behavioral activity in rats of all ages that were kept in small groups
with a
latency of 1 to 2 min. One hour after the start of exposure, the
animals were
tested in the elevated plus-maze to measure anxiety behavior. It was
found that
all age groups spent significantly more time in the open arm of the
elevated
plus-maze than the corresponding controls. Latencies to first entry
into open
arms were also significantly lowered. The number of entries to the open
or to
the dark arm, however, did not show statistical difference, indicating
that the
novel object-induced activity failed to exert influence on gross motor
activity
in the elevated plus-maze. In conclusion, the stimulation elicited by
the
exposure to novel stimulus (inanimate objects) resulted in a significant
reduction of anxiety level both in adult and in aging rats.
PMID: 11274684 [PubMed - indexed for MEDLINE]
85: Gig Sanit. 1993 Dec;(12):39-40.
[The effect of superhigh frequency electromagnetic radiation on the
central
nervous system]
The effects of low level chronic ionising irradiation (12.9 cGy/day on
the
sensory attention to the stimuli of different modalities
(somatosensory, visual,
odor) of Wistar rats were studied. Analysis of animals behaviour was
made after
they had received the different doses of irradiation: 4, 6, 8, 10, 15
and 20 Gy.
It was founded, that the attention and exploratory activity of rats is
significantly decreased up to 20-30% after 4-6 Gy. The irradiation
doses 8 Gy
did not change animal behaviour as compared to control animals, but
doses 10, 15
and 20 Gy decreased the exploratory activity as well as sensory
attention of
rats to 3-5-times as compared to previous dose. Such a wave-like way of
behaviour reflects the functioning of an adaptive mechanism.
Biochemical data
indicated that after 5 months of the irradiation (dose 20 Gy) the level
of
phospholipids, lysophosphatidylcholine, phosphatidylethanolamine,
phosphatidylcholine, cholesterol were decreased.
PMID: 9417305 [PubMed - indexed for MEDLINE]
87: Z Gesamte Hyg. 1991 Jan;37(1):4-7.
[Standardization of electromagnetic fields of 3-30 MHz with reference
to the
time factor]
Wissenschaftliches Forschungsinstitut fur Arbeitshygiene und
Berufskrankheiten,
Akademie der Medizinischen Wissenschaften, UdSSR, Moskau.
In chronic experiments (4 months) in rabbits, rats, and mice biological
effects
were investigated from 7 exposure regimen of electromagnetic fields
with a
frequency of 24 MHz at field strengths of the electric field component
of 125,
250, 500, and 1,000 V/m, respectively, and an exposure time of 0.25, 1,
and 4
hrs. respectively. The effects on the CNS, the immune and hormone
systems, the
peripheral blood and on the spermato and embryo genesis were estimated.
The
results delivered the basis for the introduction of an index. In point
of time
different limit values are to be determined according to the energetic
load. A
concrete value for the energetic load 7,200 (V/m)2.h is proposed as
maximum
allowable field strength of the electric component 300 V/m.
PMID: 2028680 [PubMed - indexed for MEDLINE]
88: Biull Eksp Biol Med. 1993 Aug;116(8):127-30.
[A new natural model of elevated anxiety in rats]
[Article in Russian]
Rodina VI, Krupina NA, Kryzhanovskii GN.
The levels of anxiety were determined in male Wistar rats using a
complex
multiparameter method for evaluating anxiety-phobic states in rats
based on
ranged scale. The effects of psychotropic drugs differed in rats with
innate
high and low levels of anxiety. Anxiolytics sodium valproate (200
mg/kg),
phenazepam (0.05 mg/kg) and diazepam (0.1 and 0.6 mg/kg) reduced
anxiety in rats
with innate high level of anxiety and prevented increase of anxiety
induced by
saline in rats with innate low level of anxiety. Pentylenetetrazol (10
mg/kg)
and haloperidol at a large dose (0.5 mg/kg) increased anxiety in rats
with
either high or low innate levels of anxiety. However sodium lactate
(600 mg/kg)
increased anxiety only in rats with innate high level of anxiety.
Haloperidol at
a small dose (0.01 mg/kg) and melipramin (10 mg/kg) were uneffective in
rats
with innate high level of anxiety. Results believed the rats with
innate high
level of anxiety to be used as a new natural animal model of anxiety.
PMID: 8274676 [PubMed - indexed for MEDLINE]
89: Indian J Exp Biol. 2000 Mar;38(3):231-6.
Hyperglycaemia in pregnancy: effects on the offspring behaviour with
special
reference to anxiety paradigms.
Ramanathan M, Jaiswal AK, Bhattacharya SK.
Department of Pharmacology, Banaras Hindu University, Varanasi, India.
Maternal hyperglycemic effect was studied on the offspring behaviour.
Offspring
were obtained from diabetic rats by mating a normal father with a
diabetic
mother (NFDM), diabetic father with normal mother (DFNM) and diabetic
father
with diabetic mother (DFDM). Rats were rendered diabetic by injecting
streptozotocin (STZ, 50 mg/kg i.p.) in citrate buffer. Offspring were
subjected
to various anxiety parameters including open field exploratory
behaviour,
elevated plus maze and zero maze behaviours, and the social interaction
tests at
the age of 8 weeks. The results indicate that offspring of NFDM and
DFDM showed
anxiogenic activity on the elevated plus maze zero maze and the social
interaction test. Offspring of NFDM and DFDM exhibited hyper and
emotional
activity in the open field behaviour test. The behavioural alterations
observed
in the offspring were comparable to the behavioural alterations noted
in STZ
diabetic rat as reported earlier. Further offspring of NFDM and DFDM
exhibited
mild hyperglycaemia. No significant behavioural alterations in the
offspring of
DFNM were observed. It may be concluded, that exposure of offspring to
diabetic
environment in their foetal life can lead to anxiogenic/emotional
behaviours in
adult life.
PMID: 10927864 [PubMed - indexed for MEDLINE]
90: Biofizika. 2000 Sep-Oct;45(5):935-40.
[Effect of modified SHF and acoustic stimulation on spectral
characteristics of
the electroencephalograms of the cat brain]
[Article in Russian]
Ivanova VIu, Martynova OV, Aleinik SV, Limarenko AV.
Ykhtomskii Research Institute of Physiology, St. Petersburg State
University,
Russia.
The effect of modulated electromagnetic fields on the spectral
parameters of
bioelectric brain activity in awake cats was studied by registering the
electroencephalogram from the skin surface in the vertex area using
carbon
electrodes. In the normal electroencephalogram, spectral components in
the range
above 20 Hz predominated. It was shown that, upon irradiation with
electromagnetic field (basic frequency 980 MHz, power density 30-50
microW/cm2),
spectral components in the range of 12-18 Hz begin to prevail. A
similarity in
the redistribution of the power of spectral components upon both
acoustic and
modulated electromagnetic influences was revealed. The results suggest
that
there is a a common neurophysiological mechanism by which modulated
electromagnetic radiation and acoustic stimulation affect the electrical
activity of the brain. This ia consistent with the assumption that the
effect of
the electromagnetic field on the central nervous system is mediated
through the
acoustic sensory system.
PMID: 11094726 [PubMed - indexed for MEDLINE]
91: Biofizika. 1996 May-Jun;41(3):762-4.
[Combined effect of variable and static magnetic fields on rat behavior
in the
"open field "]
[Article in Russian]
Deriugina ON, Pisachenko TM, Zhadin MN.
The influence of combined alternating and static magnetic fields on rat
behavior
in the "open field" test was studied. The action of the cyclotron and
Larmor
frequencies of calcium, natrium, potassium, chlorine, magnesium,
lithium, and
zinc ions was investigated. The statistically significant influence of
the
cyclotron frequencies of calcium and magnesium ions was revealed. The
calcium
frequency caused depression of investigating activity of the animals
and the
magnesium one evoked increasing moving and investigating activities.
The rest of
frequencies did not significantly act on the animal behavior.
PMID: 8924481 [PubMed - indexed for MEDLINE]
92: Med Tr Prom Ekol. 1994;(1):31-3.
[Effect of low intensity and ultra high frequency electromagnetic
irradiation on
memory functions]
[Article in Russian]
Krylova IN, Ilin AB, Dukhanin AS, Paltsev IuP, Iasnetsov VV.
The experiments on rats proved that low intensity electromagnetic waves
result
in retrograde amnesia due to benzodiazepine, gamma-aminobutyric acid and
cholinergic mechanisms. Nootropic drug pyracethamum was proved to
reduce the
pathologic effect.
PMID: 7804712 [PubMed - indexed for MEDLINE]
93: Biomed Tech (Berl). 1997;42 Suppl:103-4.
[Current status of risk discussion of low frequency electric and
magnetic fields
and high frequency electromagnetic radiation]
[Experimental study of the effects of acute uneven microwave
irradiation]
[Article in Russian]
Zuev VG, Ushakov IB.
The purpose of the study was to reveal parts of the body affected by
radiation
most of all in uneven microwave irradiation (current frequency of 2.4
GHz/s) by
the destruction criterion taking account of some indicators of the
absorbed
power of electromagnetic radiation (EMR). Uneven irradiation was
achieved by the
screening of some parts of the body with radiopaque material leaving
unshielded
parts subjected to irradiation. Control over the redistribution of
absorbed
energy was exercised by means of multichamber phantoms. In experiments
on
animals (female rats) within the range of specific absorbed power of
15-40 mWg
the utmost affection of the cranial segment was revealed. The results
show good
correlation with a curve of the effect of 50% destruction criterion in
total EMR
irradiation.
PMID: 6513752 [PubMed - indexed for MEDLINE]
95: Zh Vyssh Nerv Deiat Im I P Pavlova. 2001 Jan-Feb;51(1):114-6.
[Motor activity and emotional response in the open field test in rats
after
pharmacologic stimulation or blockade of neuropeptides in terminals of
primary
sensory neurons]
[Article in Russian]
Zhukova EM.
Institute of Physiology, Russian Academy of Sciences, Siberian Branch,
Novosibirsk.
Effects of high and low doses of capsaicin on the open-field behavioral
patterns
were examined in Wistar rats. The treated animals exhibited a
significant
increase in locomotion, grooming, and exploratory activity.
[The dependence of the biological effect of electron radiation on the
pulse
repetition rate. The characteristics of the clinical manifestations in
rats
after irradiation at superlethal doses]
[Article in Russian]
Darenskaia NG, Nasonova TA, Aleshin SN.
A comparison between biological effects of electron radiation (25 and
50 MeV) at
doses of 100-300 Gy and with pulse recurrence frequencies from 3 to
2400 s-1,
using general damage severity, distinctiveness of separate clinical
manifestations and incidence of extremely severe forms of radiation
sickness as
criteria, has demonstrated some peculiarities of radiation pathology in
rats
under these circumstances. The pulse recurrence frequency influence
varies with
the criterion applied.
Device for artifact-free recording of brain electrical activity during
exposure
of rats to UHF fields in conditions of free behavior.
Vorob'ev VV, Gorelkova TF, Konovalov VF.
Laboratory of Medical Biophysics, Russian Academy of Sciences,
Pushchino.
PMID: 9121634 [PubMed - indexed for MEDLINE]
98: Gig Sanit. 1982 Feb;(2):7-11.
[Meteorological radars as an energy source of a superhigh-frequency
range
electromagnetic field and environmental hygiene problems]
[Article in Russian]
Dumanskii IuD, Nikitina NG, Tomashevskaia LA, Kholiavko FR, Zhupakhin
KS.
PMID: 7075987 [PubMed - indexed for MEDLINE]
99: Patol Fiziol Eksp Ter. 1984 May-Jun;(3):13-6.
[Effect of a modulated UHF field on the behavior and hormone level of
female
rats under emotional stress]
[Article in Russian]
Rasulov MM.
PMID: 6540858 [PubMed - indexed for MEDLINE]
100: Indian J Exp Biol. 2001 Sep;39(9):853-7.
Effect of environmental deprivation on anxiety in rats.
Jaiswal AK.
Department of Pharmacology, Institute of Medical Sciences, Banaras Hindu
University, Varanasi, India. arunjais@rediffmail.com
Environmental deprivation (ED) induced a significant increase in
open-field
ambulation, rears, self-groomings, faecal pellets and decrease in
activity in
centre in Charles Foster albino rats of 30, 45 and 60 days age groups.
In
elevated plus maze, significant attenuation of open arm time/entries and
augmentation of enclosed arm time/entries were noted in ED rats of all
the three
age groups. Similarly ED rats also showed significant decrease in time
spent on
open arms, entries, head dips and stretched attend postures in
comparison to age
matched rats reared under normal environmental conditions. The results
indicate
that imposition of environmental deprivation in rats' life consistently
resulted
in significant anxiogenic behaviour on all the tests. However, the
anxiogenic
effect of ED was less marked when it was imposed at 60th day of life in
rats.
PMID: 11831364 [PubMed - indexed for MEDLINE]
101: Bioelectromagnetics. 2000 Dec;21(8):566-74.
Prenatal exposure to 900 MHz, cell-phone electromagnetic fields had no
effect on
operant-behavior performances of adult rats.
To clarify potential health risks of radio-frequency electromagnetic
fields
(EMFs) used in cellular telephone technology to the developing brain,
Wistar
rats were continuously exposed during pregnancy to a low-level (0.1
mW/cm(2))
900 MHz, 217 Hz pulse modulated EMF that approximated the highest legal
exposure
of normal populations to the radiation of base antennas of the GSM
digital
cell-phone technology. Whole body average specific absorption rate
(SAR) values
for the freely roaming, pregnant animals were measured in models; they
ranged
between 17.5 and 75 mW/kg. The offspring of exposed and of sham-exposed
dams
were coded and tested later as adults in a battery of ten simultaneously
operated test chambers (Skinner boxes) during night time. Eight groups
of ten
coded animals in each group were tested for learning deficits in a
sequence of
nine, computer-controlled, 15 h sessions of the food-reinforced
contingency
Differential Reinforcement of Rate with increasing performance
requirements. Two
different sets of events were recorded: The food-reinforced
lever-pressing
activity of the animals and the inter-response intervals (IRIs) between
consecutive lever presses. IRI-occurence patterns discriminated
consistently
between "learners" and "non-learners". Analyses of performance scores
and of
IRI-patterns both showed that exposure in-utero to the GSM field did
not induce
any measurable cognitive deficits. Copyright 2000 Wiley-Liss, Inc.
PMID: 11102946 [PubMed - indexed for MEDLINE]
102: Med Pr. 2000;51(6):637-52.
[Occupational exposure to electromagnetic fields and its health effects
in
electric energy workers]
[Article in Polish]
Szadkowska-Stanczyk I, Zmyslony M.
Zakladu Epidemiologii Srodowiskowej, Instytutu Medycyny Pracy w Lodzi
im. prof.
dra med. Jerzego Nofera w Lodzi.
Power frequency (50 to 60 Hz) electromagnetic fields (EMF) are briefly
characterised, EMF sources occurring in the electromagnetic industry are
discussed, and methods for and problems involved in the evaluation of
individual
occupational EMF exposure are also presented. The results of certain
cohort
industrial and case-referent studies indicate slightly enhanced risk of
brain
cancer and leukaemia in the group under study. The meta-analysis of the
results
obtained from numerous studies, published recently, showed a relative
risk (RR)
of 1.1-1.3 for leukaemia, and of 1.1-1.2 for brain cancer. Only a few
studies
demonstrate a dose-effect relationship for malignant neoplasms which
decreases
the power of the hypothesis on the cause-effect relationship. Among
health
effects of EMF exposure in electric utility workers, other than
malignant
neoplasms, an increased risk of certain diseases of the circulatory and
neurological systems has been reported. The difficulty in the
assessment of
individual exposure is the main problem in evaluating the relationship
between
EMF exposure and adverse health effects in electric utility workers. We
hope to
investigate this further.
Publication Types:
Review
Review, Tutorial
PMID: 11288692 [PubMed - indexed for MEDLINE]
103: Br J Pharmacol. 2001 Apr;132(7):1389-95.
Social isolation modifies nicotine's effects in animal tests of anxiety.
Cheeta S, Irvine E, File SE.
Psychopharmacology Research Unit, Centre for Neuroscience, GKT School of
Biomedical Sciences, King's College London, Hodgkin Building, Guy's
Campus,
London, SE1 1UL.
1. These experiments determined whether the housing conditions of rats
influenced the effects of nicotine in two animal tests of anxiety,
social
interaction and elevated plus-maze tests. 2. In animals housed singly
for 7
days, (-)nicotine (0.025 mg kg(-1) s.c.) was ineffective, but 0.05, 0.1
and 0.25
mg kg(-1) (s.c.) significantly increased the time spent in social
interaction,
without changing locomotor activity, thus indicating anxiolytic actions.
(-)Nicotine (0.45 mg kg(-1) s.c.) significantly reduced social
interaction,
indicating an anxiogenic effect. 3. However, in group-housed animals,
(-)nicotine (0.025 mg kg(-1) s.c.) had a significant anxiolytic effect
in the
social interaction test, but 0.01, 0.05, 0.1, 0.25 and 0.45 mg kg(-1)
were
ineffective. (-)Nicotine (1 mg kg(-1)) reduced motor activity and social
interaction in the group-housed animals. 4. In the elevated plus-maze,
the
time-course and the dose-response curve to nicotine were investigated.
In both
singly- and group-housed rats, (-) nicotine (0.1 - 0.45 mg kg(-1) s.c.)
decreased the per cent entries into, and per cent time spent on, the
open arms,
indicating anxiogenic effects. 5. The housing condition influenced the
time
course, with significant effects at 5 and 30 min after injection in
group-housed
rats, and significant effects at 30 and 60 min in singly-housed rats.
6. In the
social interaction test there was no difference in the scores of the
first and
last rats removed from group cages, whereas the order of removal from
the cages
did affect the scores in the elevated plus-maze. 7. These results
provide
further evidence that the two animal tests model distinct states of
anxiety, and
show how social isolation powerfully modifies both anxiolytic and
anxiogenic
effects of nicotine.
[Radioprotective effect of weak ultra-low frequency alternating
magnetic field
in adrenalectomized mice]
[Article in Russian]
Stashkov AM.
Simferopol State University, Krym, Ukraine.
PMID: 9606412 [PubMed - indexed for MEDLINE]
105: Med Tr Prom Ekol. 1998;(11):6-8.
[The evaluation of the body response of experimental animals to
exposure to the
magnetic component of electromagnetic radiation for setting a hygiene
standard]
[Article in Russian]
Bogdanov AA, Bukharin EA, Davydova OK, Plakhov NN.
Acute and subacute experiments were conducted to evaluate threshold
response of
white rats to variable magnetic intensity of magnetic section of
electromagnetic
irradiation with fixed frequency (3 MHz).
[Biological and ecological aspects of the effects combined
electromagnetic rays
on farm animals]
[Article in Russian]
Ipatova AG, Ivanov VL, Koz'min GV, Kozlov VA.
Russian Institute of Agricultural Radiology and Agroecology, Obninsk.
The study of a biological effect of ultraviolet, ultrahigh frequency and
gamma-radiation, as well as combinations of these, on the functional
status of
the sheep body systems has made it possible to evaluate the sensitivity
of a
body exposed to these factors and its adaptive potentials. The pattern
of
variations in the body systems when a combined EMR is applied depends
on to
which extent one or another factor dominates the others. It is however
possible
that the effect of the leading factor is modified by that of a less
severe
radiation, energy characteristics of which differ from those of the
dominating
factor.
PMID: 10576032 [PubMed - indexed for MEDLINE]
107: Fiziol Zh. 2003;49(1):87-93.
[Changes in reactions in rats during hypokinesia and electromagnetic
irradiation
of ultrahigh frequency]
[Article in Ukrainian]
Temur'iants NA, Chuian OM, Verko NP, Moskovchuk OB, Tumaniants OM,
Shyshko OIu,
Min'ko VA, Kurtseitova EE.
Tavritcheskiy University by V.I. Vernadsky, Sympheropol.
The effects of low intensity electromagnetic fields (EMF) on the
hypokinetic
stress were studied on rats. It has been shown that exposure to EMF,
combined
with hypokinesia or without it, prevented the typical stress reaction
on the
limited motility. EMF was determined to modify the adaptive processes
which
resulted in the adaptive activation and limiting stress reaction.
Adaptation was
characterized with lower anxiety and excitability of the central
nervous system,
and a higher level of non-specific resistance, as compared to the stress
reaction.
PMID: 12669526 [PubMed - indexed for MEDLINE]
108: Percept Mot Skills. 1999 Dec;89(3 Pt 1):1023-4.
Geophysical variables and behavior: LXXXVII. Effects of synthetic and
natural
geomagnetic patterns on maze learning.
McKay BE, Persinger MA.
Department of Psychology, Laurentian University, Ontario, Canada.
12 normal male albino rats were exposed or not exposed in their home
cages for 5
min. and 50 sec. once every hour 8 times per night to a 7-Hz square-wave
magnetic field whose amplitudes were shifted by about 50 nT
approximately every
10 sec. Although there were no statistically significant differences
between the
two groups for numbers of working errors, numbers of reference errors,
or speed
during the acquisition of an Olton (8-arm) maze, the strength of the
group
differences (F ratios) for daily working errors was reduced (rho = .70)
if there
had been enhanced geomagnetic activity during the time of the night
when the
experimental fields were present.
PMID: 10665038 [PubMed - indexed for MEDLINE]
109: Neuroreport. 2001 Oct 8;12(14):3081-4.
Hyperanxiety produced by periaqueductal gray injection of chondroitin
sulphate
glycosaminoglycan.
De Araujo JE, Hasenohrl RU, Huston JP, Brandao ML.
Laboratorio de Psicobiologia, FFCLRP, campus USP, Av. Bandeirantes 3900,
14049-901, Ribeirao Preto, SP, Brazil.
We examined the effects of chondroitin sulphate C (CSC) on fear and
anxiety
parameters following injection of the glycosaminoglycan into the dorsal
periaqueductal gray. Rats with chronically implanted cannulae were
administered
CSC (0.4 or 4.0 nmol) or vehicle (saline, 0.2 microl) and exposed to the
elevated plus-maze test of emotionality. Intra-periaqueductal gray
injection of
CSC produced a dose-dependent anxiogenic effect as indicated by reduced
entries
into and time spent on the open arms, fewer excursions into the end of
the open
arms and by increased stretched attend posture, flat back approach and
closed
arm peeping-out behaviour. The behavioural effects of CSC appeared to be
anxioselective, since the glycosaminoglycan did not influence measures
of
general (exploratory) activity, such as number of entries into the
enclosed arms
and amount of scanning, rearing and grooming. The present results show
that CSC
can produce an anxiogenic-like profile after injection into the dorsal
periaqueductal gray. This is the first such report implicating an
endogenous
matrix glycosaminoglycan in neural mechanisms governing fear and
anxiety.
Behavioral effects of buspirone in the marmoset employing a predator
confrontation test of fear and anxiety.
Barros M, Mello EL, Huston JP, Tomaz C.
Primate Center and Department of Physiological Sciences, Institute of
Biology,
University of Brasilia, Brazil, CEP 70910-900, DF, Brasilia, Brazil.
In order to further validate the recently developed marmoset (Callithrix
penicillata) predator confrontation model of fear and anxiety, we
investigated
the behavioral effects of buspirone with this method. The apparatus
consisted of
three parallel arms connected at each end to a perpendicular arm,
forming a
figure-eight continuous maze. A taxidermized wild oncilla cat (Felis
tigrina)
was positioned facing a corner of the parallel arms, alternating
between the
left or right side of the maze among animals tested. All subjects were
first
submitted to seven 30-min maze habituation trials (HTs) in the absence
of the
predator, and then to five randomly assigned treatment trials (TTs) in
the
presence of the predator: three buspirone sessions (0.1, 0.5 and 1.0
mg/kg),
saline and sham injection controls. Twenty minutes after treatment
administration, the animal was released into the maze and had free
access to the
apparatus for 30 min. All trials were taped for later behavioral
analysis.
Buspirone significantly decreased the frequency of scent marking, while
increasing the time spent in proximity to the 'predator' stimulus,
indicating an
anxiolytic effect. Neither locomotor activity, exposure to a novel
environment,
stimulus location and habituation, nor gender influenced the effects of
the drug
treatments. These results further validate this method and demonstrate
the
potential usefulness of this ethologically based paradigm to test
anxiety and
fear-induced avoidance in nonhuman primates and its susceptibility to
anxiolytic
pharmacological manipulations.
PMID: 11267630 [PubMed - indexed for MEDLINE]
111: Gig Sanit. 1992 Mar;(3):46-9.
[The sensitizing action of a high-frequency electromagnetic field]
[Article in Russian]
Nogachevskaia SI.
PMID: 1427198 [PubMed - indexed for MEDLINE]
112: Bioelectromagnetics. 1993;14(3):257-71.
Perturbations of plant leaflet rhythms caused by electromagnetic
radio-frequency
radiation.
Ellingsrud S, Johnsson A.
Department of Physics, University of Trondheim, Norway.
The minute-range up and down rhythms of the lateral leaflets of
Desmodium gyrans
has been studied when exposed to electromagnetic radiation in the
radio-frequency (RF) range. The RF radiation was applied as homogeneous
27.12
MHz fields in specially-designed exposure cells(and in some cases as
non-homogeneous radiation of 27 MHz, amplitude modulated by 50 Hz, in
front of
commercial diathermy equipment). All fields were applied as pulses. We
report
effects in the leaflet rhythms such as temporary changes in the
amplitude,
period, and phase. The radiation could also cause temporary or complete
cessations of the rhythms. The lowest dose (8 W/cm2) used was still
effective.
PMID: 8323575 [PubMed - indexed for MEDLINE]
113: Toxicol Lett. 2000 Dec 20;118(1-2):9-19.
Differential effects of low frequency, low intensity (<6 mG)
nocturnal magnetic
fields upon infiltration of mononuclear cells and numbers of mast cells
in Lewis
rat brains.
Cook LL, Persinger MA, Koren SA.
Behavioral Neuroscience Laboratory, Department of Biology, Laurentian
University, Sudbury, Ontario, Canada P3E 2C6.
Immediately after inoculation to induce experimental allergic
encephalomyelitis,
64 female Lewis rats were exposed to either a reference condition
(<10 nT) or to
one of two frequencies (7 Hz, 40 Hz) of magnetic fields whose two
intensities
(either 50 nT or 500 nT) were amplitude-modulated for 6 min once per
hour
between midnight and 8 h for 15 nights. Rats that had been exposed to
the 7 Hz,
low intensity fields displayed fewer numbers of foci of infiltrations of
mononuclear cells compared to all other groups that did not differ
significantly
from each other. Rats exposed to the 5 mG (500 nT), 40 Hz magnetic
fields
displayed more foci in the right thalamus while those exposed to the 5
mG, 7 Hz
fields displayed more foci in the left thalamus. Numbers of mast cells
within
the thalamus were also affected by the treatments. These results
suggest that
weak magnetic fields can affect the infiltration of immunologically
responsive
cells and the presence of mast cells in brain parenchyma. Implications
for the
potential etiology of 'electromagnetic sensitivity' symptoms are
discussed.
PMID: 11137304 [PubMed - indexed for MEDLINE]
114: Gig Sanit. 1986 Jul;(7):34-6.
[Biological action and hygienic significance of the electromagnetic
field
created by coastal radar facilities]
[Article in Russian]
Tomashevskaia LA, Solenyi EA.
PMID: 3758706 [PubMed - indexed for MEDLINE]
115: Braz J Med Biol Res. 2001 May;34(5):675-82.
Strain-dependent effects of diazepam and the 5-HT2B/2C receptor
antagonist SB
206553 in spontaneously hypertensive and Lewis rats tested in the
elevated
plus-maze.
Takahashi RN, Berton O, Mormede P, Chaouloff F.
Departamento de Farmacologia, Universidade Federal de Santa Catarina,
Florianopolis, SC, Brasil. takahashi@farmaco.ufsc.br
The 5-HT2B/2C receptor antagonist SB 206553 exerts anxiolytic effects
in rat
models of anxiety. However, these effects have been reported for
standard rat
strains, thus raising the issue of SB 206553 effects in rat strains
displaying
different levels of anxiety. Herein, the effects of SB 206553 in a 5-min
elevated plus-maze test of anxiety were compared to those of the
reference
anxiolytic, diazepam, in two rat strains respectively displaying high
(Lewis
rats) and low (spontaneously hypertensive rats, SHR) anxiety. Diazepam
(0.37,
0.75, or 1.5 mg/kg; 30 min before testing) increased in a
dose-dependent manner
the behavioral measures in SHR, but not in Lewis rats. On the other
hand, SB
206553 (1.25, 2.5, or 5 mg/kg; 30 min before testing) failed to alter
the
anxiety parameters in both strains, whereas it increased closed arm
entries in
Lewis rats, suggesting that it elicited hyperactivity in the latter
strain.
Accordingly, the hypolocomotor effect of the nonselective 5-HT2B/2C
receptor
agonist m-chlorophenylpiperazine (1.5 mg/kg ip 20 min before a 15-min
exposure
to an activity cage) was prevented by the 1.25 and 2.5 mg/kg doses of
SB 206553
in Lewis rats and SHR, respectively. Compared with SHR, Lewis rats may
display a
lower response to benzodiazepine-mediated effects and a more efficient
control
of locomotor activity by 5-HT2B/2C receptors.
PMID: 11323756 [PubMed - indexed for MEDLINE]
116: Vestn Akad Med Nauk SSSR. 1992;(1):38-40.
[Electromagnetic radiations from computer video terminals and their
effect on
health]
[Article in Russian]
Lazarenko NV.
The paper is concerned with a brief analysis of the reported data on
hygienic,
epidemiological and experimental estimation of the electromagnetic
radiation
(EMR) of a video-terminal (VDT). The results of the author's
investigations are
presented. Based on the data obtained it is concluded that low-intensity
wide-band EMR occurs in work places of VDT users. One should bear in
mind that
the biological action of EMR has not been studied so far.
Publication Types:
Review
Review, Tutorial
PMID: 1585729 [PubMed - indexed for MEDLINE]
117: Zh Vyssh Nerv Deiat Im I P Pavlova. 1993 Sep-Oct;43(5):1006-17.
[A multiparameter method for the complex evaluation of anxiety-phobic
states in
rats]
[Article in Russian]
Rodina VI, Krupina NA, Kryzhanovskii GN, Oknina NB.
A new multiparameter method is elaborated for evaluating the
anxiety-phobic
states in rats. The method is based on a ranged scale of parameters
which
characterize the species-specific responses of an animal to the series
of
ethologically adequate test-stimuli inducing manifestation of the
anxiety-phobic
states. The method makes it possible to evaluate an individual
anxiety-phobic
level of a rat, to form experimental groups of rats with known
individual
anxiety-phobic levels, to conduct repeated observations of the same
animals. The
method is easy to introduce into laboratory practice and makes it
possible to
obtain results quickly.
PMID: 8249450 [PubMed - indexed for MEDLINE]
118: Zh Vyssh Nerv Deiat Im I P Pavlova. 2000 May-Jun;50(3):500-8.
[Modulation of the activity of monoaminergic brain systems and emotional
condition by dalargin in rats during development of emotional resonance
response]
[Article in Russian]
Bazian AS, Orlova NV, Getsova VM.
Institute of Higher Nervous Activity and Neurophysiology, Russian
Academy of
Sciences, Moscow.
Rats were divided in two groups by the reaction of emotional resonance
(RER):
with emotionally positive reactions (I, with fast RER acquisition, up
to 100 s)
and with emotionally negative reactions (II, with slow RER acquisition,
more
than 200 s). After the RER acquisition, the activity of
5-hydroxitryptophan
(5-HT) system of the I group of animals was lower than in the II group.
The
activity of noradrenaline (NA) and dopamine (DA) systems of the I group
of
animals was higher than in the II group. The between-group differences
were
enhanced by subcutaneous injection of dalargin. In some brain structures
dalargin reversed these relations. These findings point to a complicated
interpenetrating character of emotionally positive and emotionally
negative
states. Emotionally positive states include components of emotionally
positive
states, and emotionally negative states include components of
emotionally
positive states. Increase in 5-HT activity and decrease in activity of
NA, DA,
and opioid (OP) systems induce formation of emotionally negative states.
Decrease in 5-HT activity and increase in activity of NA, DA, and OP
systems
induce formation of the emotionally positive state. It is suggested
that 5-HT,
NA, and DA systems play the central role in the processes of
reinforcement,
acquire the evaluative function, and are included in realization of all
types of
behaviors. OP is a primary modulator system which accompanies the
unconditioned
pain stimulus and connects it with systems of evaluative function.
PMID: 10923388 [PubMed - indexed for MEDLINE]
119: Pol J Pharmacol. 2001 May-Jun;53(3):245-52.
AIDA influences behavior in rats pretreated with baclofen.
Car H, Nadlewska A, Oksztel R, Wisniewski K.
Department of Pharmacology, Medical Academy, Bialystok, Poland.
The influence of the blockade of group I metabotropic glutamate
receptors (I
mGluRs) by AIDA on some behavioral effects of rats pretreated with
baclofen, an
agonist of GABA-B receptor, was investigated using behavioral tests:
the open
field, the passive avoidance response and the elevated "plus" maze.
Baclofen,
applied intraperitoneally (ip) at a dose of 0.25 mg/kg, increased the
number of
crossed fields and bar approaches in rats in the open field test, and
prolonged
the time spent in the closed arms, shortened the time spent in the open
arms and
decreased the number of entries to the open arms in the elevated "plus"
maze,
but did not affect retrieval in the passive avoidance response. AIDA
administered intracerebroventricularly (icv) alone at a dose of 100
nmol reduced
crossings and rearings in the open field test, however, it had no
effect on
retrieval in the passive avoidance situation, nor did it show any
influence in
the elevated "plus" maze. AIDA given 15 min after baclofen significantly
decreased mobility of rats (in the case of crossings to the level
observed when
AIDA was given alone), i.e. AIDA changed the effects of baclofen in the
open
field test. We also noted significant impairment of retrieval in rats
pretreated
with baclofen, which later received AIDA. AIDA significantly reduced
the effect
of baclofen on this memory process. In the elevated "plus" maze test,
AIDA did
not influence the behavior of rats pretreated with baclofen in
comparison with
the group treated with baclofen alone.
PMID: 11785925 [PubMed - indexed for MEDLINE]
120: Int J Dev Neurosci. 2001 Feb;19(1):37-45.
Prenatal stress and postnatal development of neonatal
rats--sex-dependent
effects on emotional behavior and learning ability of neonatal rats.
Nishio H, Kasuga S, Ushijima M, Harada Y.
Department of Pharmacology, Faculty of Pharmacy and Pharmaceutical
Sciences,
Fukuyama University, Fukuyama, 729-0292, Hiroshima, Japan.
nishio@fupharm.fukuyama-u.ac.jp
Maternal sound stress (800 Hz; 77 dB, every other minute for 15
min/day, from
day 10 to 18 of gestation), combined with forced swimming stress (15
min/day),
was found to cause potentiation of sound-induced loss of locomotor
activity,
referred to as emotional behavior, of male offspring, but not that of
female
offspring, at 4 weeks of age. Maternal stress also caused an increase
in the
total number of errors by male, but not female offspring in the
water-maze test
at 6 weeks of age. These effects of stress on emotional behavior and
learning
behavior were abolished when dams were pretreated with buspirone (30
min before
the stress, from day 8 to 18 of gestation). Thus, prenatal stress might
have
sex-dependent effects on emotional behavior and learning ability of
neonatal
rats.
PMID: 11226753 [PubMed - indexed for MEDLINE]
121: Biull Eksp Biol Med. 1992 Jul;114(7):52-4.
[Dynamics of calmodulin in cerebral structures under the action of
modulated UHF
electromagnetic fields]
[Article in Russian]
Katkov VF, Pavlovskii VF, Poltavchenko GM.
The influence of modulated UHF-electromagnetic fields (low intensity) on
calmodulin levels in several brain structures was studied. It was shown
that
UHF-electromagnetic fields influence calmodulin levels in the
hypothalamus and
sensorimotor cortex. Its effect depends on modulation regimes.
PMID: 1421308 [PubMed - indexed for MEDLINE]
122: Radiobiologiia. 1982 Sep-Oct;22(5):687-90.
[Effect of magnetic fields on the radiation sensitivity of mice. 1.
Effect of
infra-low frequency of magnetic fields of low intensity on survival of
experimental animals after x-ray irradiation]
[Article in Russian]
Kopylov AN, Troitskii MA.
PMID: 7178445 [PubMed - indexed for MEDLINE]
123: Neurosci Lett. 2000 Oct 13;292(3):171-4.
Suppression of experimental allergic encephalomyelitis is specific to
the
frequency and intensity of nocturnally applied, intermittent magnetic
fields in
rats.
Cook LL, Persinger MA.
Behavioral Neuroscience Laboratory and Department of Biology Laurentian
University, Sudbury, P3E 2C6, Ontario, Canada.
Female Lewis rats (n=72) were inoculated with an emulsion of spinal
cord and
complete Freund's adjuvant. They were then exposed for approximately 6
min every
hour between midnight and 08:00 h for 2 weeks to either 7 or 40 Hz
amplitude-modulated magnetic fields whose temporal pattern was designed
to
simulate a (geomagnetic) storm sudden commencement. The peak strengths
of the
fields averaged between either 30-50 nT (low intensity) or 500 nT (high
intensity). Rats exposed to the 7 Hz, low intensity magnetic fields
displayed
significantly less severe overt signs of experimental allergic
encephalomyelitis
than rats exposed to either of the two intensities of the 40 Hz fields,
the high
intensity 7 Hz field, or the reference (<10 nT) condition. The
latter groups did
not differ significantly from each other. Predicted severity based upon
the
numbers of foci of infiltrations of lymphocytes within the brains of
the rats
also demonstrated the ameliorating effects of the low intensity, 7 Hz
exposures.
These results suggest very specific characteristics of complex, weak
magnetic
fields within the sleeping environment could affect the symptoms of
autoimmunity.
Non-ionizing radiation, Part 1: static and extremely low-frequency (ELF)
electric and magnetic fields.
IARC Working Group on the Evaluation of Carcinogenic Risks to Humans.
Publication Types:
Review
Review, Academic
PMID: 12071196 [PubMed - indexed for MEDLINE]
125: Biofizika. 1996 Jul-Aug;41(4):866-9.
[Effect of extremely low frequency electromagnetic radiation and
ultra-violet
radiation on aggregation of thymocytes and erythrocytes]
[Article in Russian]
Roshchupkin DI, Kramarenko GG, Anosov AK.
Electromagnetic radiation of superhigh frequencies (46.12 and 46.19
GHz, 0.3-1
mV/cm2) at an incident dose of about 12 kJ/m2 enhances the ability of
isolated
rabbit thymocytes for aggregation interaction with homologous
erythrocytes. In
the case of 46.19 GHz frequency, the stimulatory effect disappears as
radiation
dose in increased. A radiation of 46.12 GHz stimulates thymocytes also
at high
radiation doses. Superhigh-frequency radiation enhances the sensitivity
of
thymocytes to the damaging effect of UV radiation.
PMID: 8962885 [PubMed - indexed for MEDLINE]
126: Gig Sanit. 1989 Oct;(10):82-5.
[Use of the parameters of the locomotor activity of animals in
experimental and
hygienic studies of microwave radiation]
[Article in Russian]
Navakatikian MA, Nogachevskaia SI.
PMID: 2599414 [PubMed - indexed for MEDLINE]
127: Braz J Med Biol Res. 2002 Apr;35(4):451-7.
Effects of elevated calcium on motor and exploratory activities of rats.
Godinho AF, Trombini TV, Oliveira EC.
Centro de Assistencia Toxicologica (CEATOX), Instituto de Biociencias,
Universidade Estadual Paulista, Botucatu, SP, Brasil.
godinho@ibb.unesp.br
The effects of serum and brain calcium concentration on rat behavior
were tested
by maintaining animals on either distilled water (N = 60) or water
containing 1%
calcium gluconate (N = 60) for 3 days. Animals that were maintained on
high
calcium drinking water presented increased serum calcium levels
(control = 10.12
+/- 0.46 vs calcium treated = 11.62 +/- 0.51 microg/dl). Increase of
brain
calcium levels was not statistically significant. In the behavioral
experiments
each rat was used for only one test. Rats that were maintained on high
calcium
drinking water showed increased open-field behavior of ambulation
(20.68%) and
rearing (64.57%). On the hole-board, calcium-supplemented animals showed
increased head-dip (67%) and head-dipping (126%), suggesting increased
ambulatory and exploratory behavior. The time of social interaction was
normal
in animals maintained on drinking water containing added calcium. Rats
supplemented with calcium and submitted to elevated plus-maze tests
showed a
normal status of anxiety and elevated locomotor activity. We conclude
that
elevated levels of calcium enhance motor and exploratory behavior of
rats
without inducing other behavioral alterations. These data suggest the
need for a
more detailed analysis of several current proposals for the use of
calcium
therapy in humans, for example in altered blood pressure states, bone
mineral
metabolism disorders in the elderly, hypocalcemic states, and athletic
activities.
PMID: 11960194 [PubMed - indexed for MEDLINE]
128: Neuropharmacology. 2001 May;40(6):818-25.
Leptin decreases feeding and exploratory behaviour via interactions
with CCK(1)
receptors in the rat.
Buyse M, Bado A, Dauge V.
INSERM U410, IFR02 Cellules Epitheliales, Faculte de medecine Xavier
Bichat, 16
rue Henri Huchard, 75018 Paris, France. mbuyse@bichat.inserm.fr
We assessed the effects of peripheral leptin on anxiety and exploratory
behaviour in the elevated plus-maze and in the four-hole box or Y-maze
tests, in
rats fed 80% of normal daily food intake and rats fed ad libitum. In
the Y-maze
test, i.p. injection of 0.4 or 1 mg/kg leptin into rationed rats
significantly
decreased the percentage of spontaneous alternation behaviour and
increased the
number of visits. In the elevated plus-maze test, rationed rats spent
significantly more time in the open arms (aversive part of the maze)
than did
rats fed ad libitum. This difference in behaviour was abolished by
injecting 0.4
mg/kg leptin. In the four-hole box test, i.p. administration of 1 mg/kg
leptin
significantly reduced the duration and number of hole visits in
rationed and ad
libitum fed rats. As with leptin inhibition of food intake, these
behavioural
changes caused by leptin were prevented by a CCK(1) receptor antagonist
(L364,718), at a dose that had no effect by itself. Finally, a 20-min
stress
that increased corticosterone and ACTH levels had no effect on
circulating
leptin levels and on the leptin content of epididymal fat tissue,
stomach and
brain. Thus, leptin induces hypoexploration and decreases spontaneous
alternation in rats and these effects are partly dependent on
nutritional
status. These results also suggest that the CCK system may be involved
in the
induction of these behavioural changes in rats by leptin, via the CCK(1)
receptor.
PMID: 11369035 [PubMed - indexed for MEDLINE]
129: Biomed Tech (Berl). 1997;42 Suppl:105-6.
[Exposure facilities for study of the effect of high frequency
electromagnetic
fields on biological systems]
Mother knows best: effects of maternal modelling on the acquisition of
fear and
avoidance behaviour in toddlers.
Gerull FC, Rapee RM.
Department of Psychology, Macquarie University, Sydney, NSW, Australia.
The present study was conducted to investigate the influence of parental
modelling on the acquisition of fear and avoidance towards novel,
fear-relevant
stimuli in a sample of 30 toddlers. The toddlers were shown a rubber
snake and
spider, which were alternately paired with either negative or positive
facial
expressions by their mothers. Both stimuli were presented again after a
1- and a
10-min delay, while mothers maintained a neutral expression. The
children showed
greater fear expressions and avoidance of the stimuli following negative
reactions from their mothers. This was true for both genders although
the degree
of modelled avoidance was greater in girls than in boys. The strong
observational learning results are consistent with views that modelling
constitutes a mechanism by which fear may be acquired early in life.
PMID: 11863238 [PubMed - indexed for MEDLINE]
131: Prog Clin Biol Res. 1988;257:367-76.
Possible physiological mechanisms for neurobehavioral effects of
electromagnetic
exposure.
Shandala MG.
A. N. Marzeev Research Institute of General and Communal Hygiene, Kiev,
USSR.
PMID: 3344276 [PubMed - indexed for MEDLINE]
132: Physiol Behav. 1993 Apr;53(4):827-9.
Is prolactin related to activity and emotional reactivity in rats?
Marti-Carbonell MA, Darbra S, Garau A, Sanz C, Balada F.
Department de Psicobiologia, Universitat Autonoma de Barcelona,
Bellaterra,
Catalonia, Spain.
Recent studies have shown different relationships between hormones and
personality in humans, including a relationship between prolactin
levels and
impulsivity. The aim of the present work was to study the relationships
between
basal levels of prolactin and some measures of activity and emotional
reactivity
in rats. One of the most consistent results showed a negative
correlation
between basal prolactin levels and activity. This finding is in line
with the
serotonergic theories of impulsive behavior and with the effects of
dopamine
upon activity.
PMID: 8511191 [PubMed - indexed for MEDLINE]
133: Zh Vyssh Nerv Deiat Im I P Pavlova. 1996 Nov-Dec;46(6):1109-14.
[The behavior of the progeny of prenatally irradiated rats]
[Article in Russian]
Sakharov DG, Dygalo NN.
Ambulation and rearing in the open field were decreased in adult male
offsprings
of rats which were exposed to moderate doses of gamma-irradiation
during the
last third of their intrauterine development. Single combined external
and
internal irradiation of the ancestors in the middle of the intrauterine
period
resulted in increased ambulation in the open field (and its decreased
latency)
and activity in the wheel in their adult offsprings. The obtained
evidence
suggests that exposure of parents to harmful factors has its impact on
behaviour
of offsprings depending on the characteristics of such factors.
PMID: 9054164 [PubMed - indexed for MEDLINE]
134: Int J Biometeorol. 1977 Dec;21(4):357-65.
Behavioral effects in monkeys exposed to extremely low frequency
electromagnetic
fields.
[Modification of radiosensitivity of mice by combination of alternating
magnetic
field and fractionated irradiation with small daily doses over many
days]
[Article in Russian]
Stashkov AM, Gorokhov IE.
Simferopol State University, Krym, Ukraine.
Everyday before radiation combination of weak magnetic field and
fractioned
radioactive irradiation in dose of 0.5 Gy up to total doses of 6.0-8.0
Gy
increased surviving of mice by 34-53%, prolonged the life-time 1.5
times as much
(half as much). It also decreased the rate of accumulation of damaged
systems,
extended average time of death and the value of dose changing factor,
and
reduced the gradient of damaged systems.
PMID: 9606413 [PubMed - indexed for MEDLINE]
136: Physiol Behav. 2000 Dec;71(5):509-16.
Behavioral profile of wild mice in the elevated plus-maze test for
anxiety.
Holmes A, Parmigiani S, Ferrari PF, Palanza P, Rodgers RJ.
Dipartimento di Biologia Evolutiva e Funzionale, Universita di Parma,
Viale di
Scienze, 43100, Parma, Italy. aholmes@codon.nih.gov
Systematic observations of the defensive behavior of wild rodents have
greatly
informed the experimental study of anxiety and its neural substrates in
laboratory animals. However, as the former work has been almost
exclusively
carried out in rats, few data are available concerning the reactivity
of wild
mice to standardized tests of anxiety-related behavior. In the present
experiments, we employed ethological measures to examine the behavioral
responses of a wild-derived population of house mice (Mus musculus) in
the
elevated plus-maze. In direct comparisons with laboratory Swiss mice,
male wild
mice exhibited substantially elevated levels of exploratory activities
and an
overall "preference" for the open arms of the plus-maze. On re-exposure
to the
plus-maze, male wild mice showed further increases in open arm
exploration,
while Swiss mice showed a marked shift to the enclosed parts of the
plus-maze.
Tested over a single session, female wild mice also exhibited a profile
of high
open arm exploration, but showed levels of exploratory behaviors and
locomotor
activity similar to female Swiss counterparts. While exploratory
patterns in
wild mice show similarities to profiles seen in certain laboratory
strains
(e.g., BALB/c), wild mice displayed a number of additional behaviors
that are
unprecedented in plus-maze studies with laboratory mice. These included
actual
and attempted jumps from the maze, spontaneous freezing, and
exploration of the
upper ledges of the closed arms. Thus, while in conventional terms the
behavior
of wild mice was consistent with one of low anxiety-like behavior, the
presence
of these unique elements instead indicates a profile more accurately
characterized by high reactivity and escape motivation. We discuss how
the use
of an ethological approach to measuring plus-maze behavior can support
accurate
interpretation of other exceptional profiles in this test, such as those
possibly arising from phenotyping of transgenic and gene knockout mice.
PMID: 11239669 [PubMed - indexed for MEDLINE]
137: DLR Nachr. 1996 Feb;81:22-6.
[Effect of low-frequency magnetic fields on the orientation behavior of
unicellular organisms: new findings on the biological effect of
electromagnetic
alternating fields]
[Article in German]
Becker E, Hemmersbach R, Stockem W.
Institut fur Zellbiologie der Universitat, Bonn.
PMID: 11542970 [PubMed - indexed for MEDLINE]
138: Bioelectromagnetics. 2001 Apr;22(3):200-4.
Why arguments based on photon energy may be highly misleading for power
line
frequency electromagnetic fields.
Vistnes AI, Gjotterud K.
Department of Physics, University of Oslo, Oslo, Norway.
a.i.vistnes@fys.uio.no
When evaluating possible mechanisms by which low frequency
electromagnetic
fields may have a biological effect, arguments based on photon energy
have often
been used in a misleading way. For visible light the concept of photons
has
proved to be very useful in explaining experimental findings. However,
the
concept of photons cannot be used without major modifications in
describing
phenomena related to near field problems at power frequency (50 or 60
Hz)
electric and magnetic fields. For this regime, the photon description
is very
complex. A very high number of highly coherent photons must be used in
a quantum
electrodynamic description of low frequency electromagnetic field
phenomena.
Thus, one-photon interaction descriptions must be replaced by
multiple-photon
interaction formalism. However, at low frequencies, a classical
electromagnetic
field description is far more useful than quantum electrodynamics.
There is in
principle no difference in how much energy an electron can pick up from
a low
frequency electric field as compared to from a high frequency photon.
Thus, the
total gain in energy is not limited to the energy carried by a single
photon,
which is E = hv, where h is Planck's constant and (v) is the frequency
of the
radiation. However, the time scale of the primary event in a mechanism
of action
is very different for ionizing radiation compared to power line
frequency
fields. The advice is to consider the time scale given by the inverse
of the
frequency of the fields, rather than photon energy, when one use
physics as a
guidance in evaluating possible mechanisms for biological effects from
low
frequency electromagnetic fields. Copyright 2001 Wiley-Liss, Inc.
Different effects of diazepam in Fischer rats and two stocks of Wistar
rats in
tests of anxiety.
Bert B, Fink H, Sohr R, Rex A.
Institute of Pharmacology and Toxicology, School of Veterinary
Medicine, Freie
Universitat Berlin, Koserstr. 20, D-14195 Berlin, Germany.
The behaviour of animals in tests of anxiety varies between strains,
even in
identical tests and surroundings. To evaluate the results obtained, a
more
detailed knowledge of the behaviour of different rat strains is
indispensable.
Identically raised Fischer 344 rats and two stocks of Wistar rats were
examined
in two animal tests of anxiety: the X-maze and a modified open-field
test
following diazepam treatment (0.5-4.0 mg/kg). Harlan-Wistar rats were
the least
'anxious' when the behaviour of vehicle treated controls was compared.
The
largest effect of the anxiolytic diazepam, however, was observed in
Harlan-Fischer rats. To determine possible reasons for strain and stock
differences, plasma concentrations of diazepam and metabolites and
concentrations of serotonin (5-HT) in the CNS were measured. Plasma
concentrations of diazepam and metabolites differed between the strains
with the
Harlan-Fischer rats showing higher diazepam concentrations. 5-HT levels
in
discrete brain regions varied with Harlan-Fischer rats having higher
5-HT
concentrations. Strain differences influence the anxiety-associated
behaviour of
untreated animals and the effect of anxiolytics.
PMID: 11701214 [PubMed - indexed for MEDLINE]
140: Bangladesh Med Res Counc Bull. 2000 Apr;26(1):27-32.
Isolation modifies the behavioural response in rats.
Karim A, Arslan MI.
Pharmacology Department, SSMC, Mitford, Dhaka.
Twenty-four male wister rats were reared from weaning either alone
(isolation
reared) or in groups of five (socially reared) for 6 weeks. Thereafter,
the
present study examined and compared the behaviour of isolation and
socially
reared rats in the test of social interaction, in the elevated
plus-maze test of
anxiety, in the open field behavior of exploration and locomotion
activity, and
the depressive behaviour in forced swim test. Under high light in
unfamiliar
conditions isolation reared rats spent significantly more time in
aggressive
interactions (P < 0.05) and high levels of aggressive behaviour
compared to the
socially reared rats (P < 0.05). Isolation reared rats had spent
less time in
the open arms than the socially reared rats in the maze test (P <
0.05).
Isolation reared rats were more exploratory than the socially reared
rats in the
open field test and the defaecation scores were less compared to the
socially
reared controls (P < 0.05). Isolated rats spent less time immobile
on the rats'
forced swim test behaviour but the difference was not statistically
significant.
These findings suggest that isolation reared rats are nervous,
aggressive and
hyperactive animals in a novel field. It appears that isolation rearing
in the
early stages of life has modified a variety of behaviour in the adult
rats, and
the investigation of the pattern of behavioural changes in isolation
reared rats
may help to explore the environmental influences on the development of
human
psychopathology.
PMID: 11192492 [PubMed - indexed for MEDLINE]
141: Vrach Delo. 1983 Mar;(3):109-11.
[Effect of different doses of a UHF field on the morphofunctional state
of the
kidneys]
[Article in Russian]
Belokrinitskii VS, Grin' AN.
PMID: 6858083 [PubMed - indexed for MEDLINE]
142: Neurobiol Learn Mem. 2002 Jul;78(1):11-22.
Fischer 344 and wistar rats differ in anxiety and habituation but not
in water
maze performance.
Bert B, Fink H, Huston JP, Voits M.
Institute of Pharmacology and Toxicology, School of Veterinary
Medicine, Free
University Berlin, Koserstr. 20, Berlin, 14195, Germany.
bertb@zedat.fu-berlin.de
The fact that various neuropharmacological substances have anxiolytic
as well as
amnesic effects suggests that neuronal mechanisms of anxiety and
learning/memory
closely interact. Hence, we hypothesized that differences in
anxiety-related
behavior could be accompanied with differences in cognition or
habituation. Two
rat strains with different levels of anxiety, more anxious Fischer 344
rats by
Charles River (FC) and less anxious Wistar rats by Winkelmann (WW),
were tested
in the Morris water maze task and an open field test for habituation
learning.
Additionally, we investigated the effect of different light intensities
on the
performance in the Morris water maze and the elevated plus maze. The
results of
the water maze task indicate that differences in anxiety-related
behavior do not
go along with differences in this performance of learning/memory.
Moreover, the
test was not affected by different light intensities. In contrast,
illumination
did affect performance in the elevated plus maze test, wherein dim light
provoked an anxiolytic effect in both rat strains. The findings that
neither
different baseline levels of anxiety nor fear modulating light
conditions were
accompanied by changes in the performance of rats in the Morris water
maze led
us to the suggestion that there is no connection between anxiety and
learning/memory in this task. Contrarily, anxiety might be associated
with
habituation learning in the open field test, shown by the superior
habituation
of the anxious FC rats in comparison to the less anxious WW rats. In
sum, these
results indicate that anxiety and learning/memory seem to be
independently
regulated behaviors, whereas habituation might be more closely
correlated with
anxiety. Nevertheless, a general statement about the relation between
emotionality and learning/memory mechanisms would be premature and the
link
between behaviors remains to be clarified. Copyright 2002 Elsevier
Science
(USA).
PMID: 12071664 [PubMed - indexed for MEDLINE]
143: Physiol Behav. 1999 Jan 1-15;65(4-5):753-61.
Corrected and republished in:
Physiol Behav. 1999 Sep;67(3):753-61.
Ultrawide-band electromagnetic pulses induced hypotension in rats.
Lu ST, Mathur SP, Akyel Y, Lee JC.
McKesson BioServices, U.S. Army Medical Research Detachment, Microwave
Bioeffects Branch, Brooks Air Force Base, TX 78235, USA.
shin-tsu.lu@aloer.brooks.af.mil
The ultrawide-band (UWB) electromagnetic pulses are used as a new
modality in
radar technology. Biological effects of extremely high peak E-field,
fast rise
time, ultrashort pulse width, and ultrawide band have not been
investigated
heretofore due to the lack of animal exposure facilities. A new
biological
effects database is needed to establish personnel protection guidelines
for
these new type of radiofrequency radiation. Functional indices of the
cardiovascular system (heart rate, systolic, mean, and diastolic
pressures) were
selected to represent biological end points that may be susceptible to
the UWB
radiation. A noninvasive tail-cuff photoelectric sensor
sphygmomanometer was
used. Male Wistar-Kyoto rats were subjected to sham exposure, 0.5-kHz
(93 kV/m,
180 ps rise time, 1.00 ns pulse width, whole-body averaged specific
absorption
rate, SAR = 70 mW/kg) or a 1-kHz (85 kV/m, 200 ps rise time, 1.03 ns
pulse
width, SAR = 121 mW/kg) UWB fields in a tapered parallel plate GTEM
cell for 6
min. Cardiovascular functions were evaluated from 45 min to 4 weeks
after
exposures. Significant decrease in arterial blood pressures
(hypotension) was
found. In contrast, heart rate was not altered by these exposures. The
UWB
radiation-induced hypotension was a robust, consistent, and persistent
effect.
PMID: 10073476 [PubMed - indexed for MEDLINE]
144: Lik Sprava. 1992 Oct;(10):69-71.
[The brain function of animals exposed to the action of centimeter
electromagnetic waves]
[Article in Russian]
Smolia AL, Bezdol'naia IS.
It was established that centimeter electromagnetic waves (EMW) are a
biologically active factor. Dynamic of changes of behavioural reactions
under
the effect of EMW evidences instability of the functional state of the
brain EMW
densities of 1000, 1500 mW/cm2 produce a response characterized by
inhibition of
motor activity.
Cannabinoid effects on anxiety-related behaviours and hypothalamic
neurotransmitters.
Arevalo C, de Miguel R, Hernandez-Tristan R.
Departamento de Biologia Animal II (Fisiologia Animal), Facultad de
Biologia,
Universidad Complutense, 28040, Madrid, Spain.
The aim of the present study was to examine the effects of the
cannabinoid
agonist CP 55,940 and the antagonist SR 141716A, alone and in
combination, on
rat exploratory and anxiety-like behaviour in the holeboard and elevated
plus-maze tests. A further aim was to evaluate the effects of these
treatments
on hypothalamic neurotransmitters. Animals treated with CP 55,940 doses
of 0.125
and 0.1 mg/kg exhibited less exploration and an increase in anxiety-like
behaviour accompanied by great motor inhibition. No hypoactivity was
seen at
0.075 mg/kg dosage, but anxiety and neophobic responses persisted,
indicating
independent and specific effects. Motor activity effects induced by CP
55,940
were reversed by pretreatment with SR 141716A (3 mg/kg). Surprisingly,
when
administered on its own, the antagonist also induced a reduction in
exploratory
parameters and an increase in anxiety-like responses. These apparently
similar
effects might be caused by different neural mechanisms. Finally, CP
55,940
increased hypothalamic dopamine and serotonin levels. These increases
might be
involved in the activation of the hypothalamic-pituitary-adrenal axis
described
for cannabinoids.
PMID: 11566149 [PubMed - indexed for MEDLINE]
146: Physiol Behav. 1999 Sep;67(3):753-61.
Corrected and republished from:
Physiol Behav. 1999 Jan 1-15;65(4-5):753-61.
Ultrawide-band electromagnetic pulses induced hypotension in rats.
Lu ST, Mathur SP, Akyel Y, Lee JC.
McKesson BioServices, U.S. Army Medical Research Detachment, Microwave
Bioeffects Branch, Brooks Air Force Base, TX 78235, USA.
shin-tsu.lu@aloer.brooks.af.mil
The ultrawide-band (UWB) electromagnetic pulses are used as a new
modality in
radar technology. Biological effects of extremely high peak E-field,
fast rise
time, ultrashort pulse width, and ultrawide band have not been
investigated
heretofore due to the lack of animal exposure facilities. A new
biological
effects database is needed to establish personnel protection guidelines
for
these new type of radiofrequency radiation. Functional indices of the
cardiovascular system (heart rate, systolic, mean, and diastolic
pressures) were
selected to represent biological end points that may be susceptible to
the UWB
radiation. A noninvasive tail-cuff photoelectric sensor
sphygmomanometer was
used. Male Wistar-Kyoto rats were subjected to sham exposure, 0.5-kHz
(93 kV/m,
180 ps rise time, 1.00 ns pulse width, whole-body averaged specific
absorption
rate, SAR = 70 mW/kg) or a 1-kHz (85 kV/m, 200 ps rise time, 1.03 ns
pulse
width, SAR = 121 mW/kg) UWB fields in a tapered parallel plate GTEM
cell for 6
min. Cardiovascular functions were evaluated from 45 min to 4 weeks
after
exposures. Significant decrease in arterial blood pressures
(hypotension) was
found. In contrast, heart rate was not altered by these exposures. The
UWB
radiation-induced hypotension was a robust, consistent, and persistent
effect.
Publication Types:
Corrected and Republished Article
PMID: 10497968 [PubMed - indexed for MEDLINE]
147: Zh Vyssh Nerv Deiat Im I P Pavlova. 2001 May-Jun;51(3):324-8.
[Analysis of possibility of genotypic correlation between fear and
anxiety]
[Article in Russian]
Khrapova MV, Popova NK, Avgustinovich DF.
Institute of Cytology and Genetics, Russian Academy of Sciences,
Siberian
Branch, Novosibirsk.
Special features of anxious behavior in the elevated plus maze test and
acoustic
startle response were analyzed in 11 inbred mouse strains. A significant
influence of the genotype both on the startle amplitude and behavior in
the
elevated plus maze was found. However, analysis of covariance did not
reveal a
genotype-related association between anxiety and startle amplitude. The
data
indicates that the fear-induced acoustic startle response and anxious
behavior
in the elevated plus maze (agoraphobia) are not genetically related.
PMID: 11550640 [PubMed - indexed for MEDLINE]
148: Shinrigaku Kenkyu. 1997 Dec;68(5):339-45.
[A temporary reduction of emotional reactivity in postweaning,
prejuvenile rats:
examination by the Runway Test]
[Article in Japanese]
Miyamoto K.
Department of Psychology, Faculty of Letters, Tokai Women's College,
Kakamigahara, Japan.
Developmental change of emotional reactivity in Wistar rats was
investigated by
two experiments using the Runway Test. Rats were tested at 20, 30, 40,
60, and
90 days of age for three successive days. First, a cross-sectional
comparison of
behavior in the Runway Test showed that 30-day-old rats were faster to
enter the
runway region, faster to reach the end section, and traversed more
sections than
other age groups. Rats at 60 and 90 days of age defecated more bolles
and
urinated more. Second, longitudinal comparisons showed that the
ambulation of
30- and 40-day-old rats increased gradually over test days, suggesting
lowered
emotional reactivity. But 60- and 90-day-old rats showed asymptotic
level of
ambulation and no increase between days and less defecation. These
results
suggested that postweaning prejuvenile rats showed a temporary
reduction of
emotional reactivity in novel environments. Also, their emotional
reactivity
elevated gradually, and remained stable in each individual level.
PMID: 9551536 [PubMed - indexed for MEDLINE]
149: Brain Res Dev Brain Res. 2001 Aug 23;129(2):189-99.
Prenatal exposure to ethinylestradiol elicits behavioral abnormalities
in the
rat.
Dugard ML, Tremblay-Leveau H, Mellier D, Caston J.
Laboratoire PSY.CO, U.F.R. de Psychologie, Universite de Rouen, 76821
Mont-Saint-Aignan Cedex, France.
Pregnant rats were i.p. injected with a solution of
17alpha-ethinylestradiol (15
microg kg(-1)) every day between day 9 and day 14 of pregnancy and the
behavior
of the offspring was compared to that of rats born from dams injected
with the
vehicle only during the same gestational period. The percentage of
neonatal
death was dramatically high in the prenatally treated group. Growth of
the
surviving animals was even better than that of controls, but when
adult, they
exhibited a number of behavioral abnormalities: increased spontaneous
motor
activity, decreased exploratory behavior, impaired cognitive processing,
qualitatively different exploratory drive, and/or persevering behavior,
increased anxiety-like behavior and social neophobia. These behavioral
alterations, which resemble a number of psychiatric syndromes, suggest
that
ethinylestradiol altered the ontogenesis of different parts of the
central
nervous system involved in cognitive and emotional processes. However,
it cannot
be excluded that the changes in behavior of ethinylestradiol exposed
offspring
were due to the abnormal maternal behavior of the estradiol treated
dams.
PMID: 11506863 [PubMed - indexed for MEDLINE]
150: Gig Sanit. 1982 Oct;(10):38-41.
[Genetic hazard of microradiowaves of nonheat intensity and its hygienic
aspects]
[Article in Russian]
Shandala MG, Antipenko EN, Koveshnikova IV, Timchenko OI.
PMID: 7173645 [PubMed - indexed for MEDLINE]
151: Radiobiologiia. 1986 May-Jun;26(3):365-71.
[Systemic effects of the interaction of an organism and microwaves]
[Article in Russian]
Suvorov NB, Vasilevskii NN, Ur'iash VV.
A study was made of the dynamics of neurophysiological processes, the
autonomic
nervous system reactions, and the behaviour of cats during long-term
electromagnetic field (EMF) exposure (500 mu W/cm2, 2375 MHz). Revealed
were the
synchronization of the brain bioelectrical activity at 6-10 Hz and
12-16 Hz,
different EMF sensitivity of the brain structures, the heart rate
decrease, and
the increase in the mobility and aggression of the animals. A complex of
interrelated changes occurring virtually in all functional systems of
the
organism should be considered as a specific EMF effect.
PMID: 3737885 [PubMed - indexed for MEDLINE]
152: Biull Eksp Biol Med. 1980 Nov;90(11):602-5.
[Effect of fluctuating electromagnetic fields on the processes of
growth and
blastomogenesis]
[Article in Russian]
Iur'ev VN, Krasnogorskaia NV.
Rats were exposed to low-frequency electromagnetic field, adequate to
the
natural background, with Gaussian energy distribution, spectrum width
15 kHz,
and field intensity 5 V/cm. Electric fluctuations were shown to have an
inhibitory action on the normal growth of the animals and on blastoma
development. This action reaches maximum with the greatest build-up
gradient. As
the frequency band of the field of action increase, the inhibitory
effect
declines.
Active immunization of white rats with cholecystokinin-4 covalently
linked to
the antigen carrier BSA evoked long-lasting changes in the rats'
behavior, which
were in the opposite direction to the anxiogenic effects of
cholecystokinin-4
itself, showing that immunization had anxiolytic effects. Immunoenzyme
analysis
demonstrated the presence of antibodies to cholecystokinin-4 in the
serum of
immunized rats. These data are interesting from the point of view of
correcting
pathological anxiety and fear states by inverse immunoregulation.
PMID: 11942698 [PubMed - indexed for MEDLINE]
154: Genome Res. 2002 Apr;12(4):618-26.
A quantitative trait locus influencing anxiety in the laboratory rat.
Fernandez-Teruel A, Escorihuela RM, Gray JA, Aguilar R, Gil L,
Gimenez-Llort L,
Tobena A, Bhomra A, Nicod A, Mott R, Driscoll P, Dawson GR, Flint J.
Medical Psychological Unit, School of Medicine, Universitat Autonoma de
Barcelona, Barcelona E-08143, Spain.
A critical test for a gene that influences susceptibility to fear in
animals is
that it should have a consistent pattern of effects across a broad
range of
conditioned and unconditioned models of anxiety. Despite many years of
research,
definitive evidence that genetic effects operate in this way is
lacking. The
limited behavioral test regimes so far used in genetic mapping
experiments and
the lack of suitable multivariate methodologies have made it impossible
to
determine whether the quantitative trait loci (QTL) detected to date
specifically influence fear-related traits. Here we report the first
multivariate analysis to explore the genetic architecture of rodent
behavior in
a battery of animal models of anxiety. We have mapped QTLs in an F2
intercross
of two rat strains, the Roman high and low avoidance rats, that have
been
selectively bred for differential response to fear. Multivariate
analyses show
that one locus, on rat chromosome 5, influences behavior in different
models of
anxiety. The QTL influences two-way active avoidance, conditioned fear,
elevated
plus maze, and open field activity but not acoustic startle response or
defecation in a novel environment. The direction of effects of the QTL
alleles
and a coincidence between the behavioral profiles of anxiolytic drug
and genetic
action are consistent with the QTL containing at least one gene with a
pleiotropic action on fear responses. As the neural basis of fear is
conserved
across species, we suggest that the QTL may have relevance to trait
anxiety in
humans.
A detailed ethological analysis of the mouse open field test: effects of
diazepam, chlordiazepoxide and an extremely low frequency pulsed
magnetic field.
Choleris E, Thomas AW, Kavaliers M, Prato FS.
Room 9222D, Department of Psychology, Social Science Center, University
of
Western Ontario, London, Ontario, Canada N6A 5C2. choleris@julian.uwo.ca
The open field test (OFT) is a widely used procedure for examining the
behavioral effects of drugs and anxiety. Detailed ethological
assessments of
animal behavior are lacking. Here we present a detailed ethological
assessment
of the effects of acute treatment with the benzodiazepines, diazepam
(DZ,
1.5mg/kg) and chlordiazepoxide (CDP, 5.0 and 10.0mg/kg), as well as
exposure to
a non-pharmacological agent, a specific pulsed extremely low frequency
magnetic
field (MAG) on open field behavior. We examined the duration, frequency
and time
course of various behaviors (i.e. exploration, walk, rear, stretch
attend,
return, groom, sit, spin turn, jump and sleep) exhibited by male mice in
different regions of a novel open field. Both DZ and CDP consistently
reduced
the typical anxiety-like behaviors of stretch attend and wall-following
(thigmotaxis), along with that of an additional new measure: 'returns',
without
producing any overall effects on total locomotion. The drugs also
differed in
their effects. CDP elicited a shift in the locomotor pattern from a
'high
explore' to a 'high walk', while DZ mainly elicited alterations in sit
and
groom. The MAG treatment was repeated twice with both exposures reducing
horizontal and vertical (rearing) activity and increasing grooming and
spin
turns. However, the anxiety-like behaviors of stretch attend and return
were
marginally reduced by only the first exposure. We conclude that a
detailed
ethological analysis of the OFT allows not only the detection of
specific
effects of drugs and non-pharmacological agents (i.e. pulsed magnetic
field) on
anxiety-like behaviors, but also permits the examination of non-specific
effects, in particular those on general activity.
PMID: 11378179 [PubMed - indexed for MEDLINE]
156: Ann Ist Super Sanita. 2001;37(2):213-24.
[Infantile leukemia and exposure to 50/60 Hz magnetic fields: review of
epidemiologic evidence in 2000]
[Article in Italian]
Lagorio S, Salvan A.
Laboratorio di Igiene Ambientale, Istituto Superiore di Sanita, Roma.
We review the epidemiological evidence on childhood leukemia and
residential
exposure to 50/60 Hz magnetic fields. The possibility of carcinogenic
effects of
power frequency magnetic fields (ELF-EMF), at levels below units of
micro tesla
(microT), was first raised in 1979 by a case-control study on childhood
cancer
carried out in Denver, USA. In that study, excess risks of total cancer
and
leukemia were observed among children living in homes with "high or
very high
current configuration", as categorised on the basis of proximity to
electric
lines and transformers. Many other epidemiological studies have been
published
since then, characterised by improved--although still not
optimal--methods of
exposure assessment. At the end of 2000, the epidemiological evidence
to support
the association between exposure to extremely-low-frequency magnetic
fields and
the risk of childhood leukemia is less consistent than what was
observed in the
mid 90s. At the same time, a growing body of experimental evidence has
accumulated against both a direct and a promoting carcinogenic effect of
ELF-EMF. Such "negative" experimental evidence hampers a causal
interpretation
of the "positive" epidemiological studies.
Publication Types:
Review
Review, Tutorial
PMID: 11758279 [PubMed - indexed for MEDLINE]
157: Eur J Neurosci. 2002 Apr;15(7):1206-18.
Contribution of amygdala neurons containing peptides and calcium-binding
proteins to fear-potentiated startle and exploration-related anxiety in
inbred
Roman high- and low-avoidance rats.
Yilmazer-Hanke DM, Faber-Zuschratter H, Linke R, Schwegler H.
The purpose of this study was to investigate amygdala-related fear and
anxiety
in two inbred rat lines differing in emotionality (RHA/Verh and
RLA/Verh), and
to relate the behaviour of the animals to neuronal types in different
nuclei of
the amygdala. The behavioural tests used were the motility test,
elevated
plus-maze and fear-potentiated startle response. The neurons
investigated were
immunoreactive for the anxiogenic peptide corticotropin-releasing factor
(CRF-ir), the anxiolytic peptide neuropeptide Y (NPY-ir), and the
calcium-binding proteins parvalbumin (PARV-ir) and calbindin (CALB-ir).
The
NPY-ir, PARV-ir and CALB-ir neurons studied were subpopulations of
GABAergic
neurons. RLA/Verh rats, which showed a significant fear-potentiation of
the
acoustic startle response, had more CRF-ir projection neurons in the
central
nucleus of the amygdala. The same RLA/Verh rats were either less or
equally
anxious in the motility test (similar to open field) and elevated
plus-maze as
compared with RHA/Verh rats. In accordance with this behaviour, the
RLA/Verh
rats had more NPY-ir neurons in the lateral, and more PARV-ir neurons
in basal
nuclei of the amygdala than RHA/Verh rats, but no differences were
detected in
the number of CRF-ir and CALB-ir neurons of the basolateral complex. In
conclusion, the RLA/Verh rats displayed an opposite behaviour in the
fear-potentiated startle model and the exploratory tests measuring
anxiety based
on choice behaviour. Thus, the anxiogenic systems in the central
nucleus and
anxiolytic systems in the basolateral complex of the amygdala might be
differentially involved in the fear-potentiated startle paradigm and
exploratory
tests in the Roman rat lines.
PMID: 11982631 [PubMed - indexed for MEDLINE]
158: Lik Sprava. 1998 Oct-Nov;(7):71-3.
[The effect of ultrahigh-frequency radiation on adaptation thresholds
and the
damages to blood system cells]
[Article in Ukrainian]
Obukhan KI.
Cytologic investigations designed to study bone marrow, peripheral
blood,
spleen, and thymus of albino rats irradiated by an electromagnetic
field, 2375,
2450, and 3000 MEGS, revealed structural and functional changes in
populations
of megakaryocytes, immunocompetent cells as well as of undifferentiated
cells,
and of other types of cells that are dependent on the intensity of
irradiation
and permit establishing the probability-threshold levels of exposure
taking
account of reactions of perception and physiologic adaptation together
with
compensatory and regenerative processes and the injury sustained. It is
shown
that changes in bone marrow cells differentiation and reproduction
rather than
integral shifts in the peripheral blood that acquire the utmost
significance.
Subjected to a particular scrutiny in the paper are blast cells, which
cells'
repopulation was noted to be getting increased in low-intensity
exposure as were
disturbances in their mitosis pattern.
PMID: 10050464 [PubMed - indexed for MEDLINE]
159: Zh Vyssh Nerv Deiat Im I P Pavlova. 1999 Mar-Apr;49(2):321-30.
[Changes in the behavior and EEG of rats administered penicillin and a
physiological solution into the amygdalar basal nuclei]
[Article in Russian]
Pankova NB, Kryzhanovskii GN, Kuznetsov IuB, Latanov AV.
Institute of General Pathology and Pathophysiology, Russian Academy of
Medical
Sciences, Moscow.
Three weeks after implantation of the electrodes for EEG recording,
hyperactivation of the basal nucleus of rat's amygdala was produced by
a local
injection of penicillin (0.5 mcl, 1% solution). Saline injection of the
same
volume served as control. The hyperactivation of the amygdala resulted
in a
long-lasting (at least for 3 weeks) increase in the locomotor activity
against
the background and deficit in exploratory behavior and rise of the
level of
anxiety and fear. The behavioral changes were accompanied by a long-term
disruption of the hippocampal theta rhythm, appearance and slowing of
the
immobility-related high-voltage spindles, and increase in the EEG
dominant
frequency in the state of emotional tension. Saline injection led to a
short-time (up to 1 week) decrease in locomotor and exploratory
activity and
increase in anxiety. These phenomena were accompanied by a short-time
disruption
of the theta rhythm and appearance of the 10-13-Hz oscillations
characteristic
for the state of emotional tension.
PMID: 10486901 [PubMed - indexed for MEDLINE]
160: Pol J Pharmacol. 2001 May-Jun;53(3):235-43.
Examination of the influence of 3,5-DHPG on behavioral activity of
angiotensin
II.
Holy Z, Wisniewski K.
Department of Pharmacology, Medical Academy of Bialystok, Poland.
The effects of the class I metabotropic glutamate receptor (mGluR)
stimulation
on the behavioral activity of angiotensin II (Ang II) was investigated
in the
present study. The experiments were performed on adult male Wistar rats.
Stimulation of the group I of mGluR receptors was evoked by icv
injection of
(S)-3,5-dihydroxyphenylglycine (3,5-DHPG) at the dose of 0.01 and 1
nmol per
rat. Fifteen minutes later, the animals were given icv solution
containing 1
nmol of Ang II. Memory motivated affectively was evaluated in passive
avoidance
and active avoidance responses (CARs). Moreover, the speculative
influence of
the treatment on anxiety and motor activity was tested in elevated
plus-maze and
in open field, respectively. We observed that both compounds did not
have
statistically significant influence on motor activity of rats in open
field
test. However, 3,5-DHPG at the dose of 0.01 nmol given alone and
combined with
Ang II tended to increase locomotor activity. 3,5-DHPG, given alone,
significantly facilitated consolidation process in a passive avoidance
situation
(only at the dose of 0.01 nmol) but had no influence on acquisition and
recall
of information. Examination of the influence of 3,5-DHPG on the
acquisition and
extinction of CAR proved that it did not alter acquisition and
extinction of
these responses. In the elevated plus-maze, 3,5-DHPG had anxiogenic-like
profile. Ang II, as repeatedly shown before, greatly increased passive
avoidance
latency, rate of acquisition of CARs and decreased their extinction. On
the
other hand, Ang II induced anxiolytic-like effect in elevated
plus-maze. The
pre-treatment of rats with 3,5-DHPG tended to attenuate behavioral
effects of
the Ang II administration.
Effects of central noradrenaline depletion by the selective neurotoxin
DSP-4 on
the behaviour of the isolated rat in the elevated plus maze and water
maze.
Lapiz MD, Mateo Y, Durkin S, Parker T, Marsden CA.
School of Biomedical Sciences, University of Nottingham Medical School,
Queen's
Medical Centre, UK.
RATIONALE: Social isolation of the rat from weaning influences behaviour
following central noradrenaline (NA) depletion by the selective
neurotoxin
N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4). OBJECTIVES: The
study
characterised the effects of DSP-4 on the behaviour of isolates in the
elevated
plus maze and water maze. METHODS: Male Lister hooded rats were reared
singly or
in groups after weaning. Two weeks postweaning, the rats were injected
with
DSP-4 (25 mg/kg, i.p.) or saline. From week 4, rats were tested in the
plus maze
and in the water maze. RESULTS: DSP-4 significantly reduced cortical and
hippocampal NA but had no effect on hypothalamic NA. Isolation rearing
alone had
no significant effects on behaviour in the elevated plus maze but
enhanced
retention of platform placement in the water maze as measured by
increased
entries to the platform annulus during the probe test. DSP-4 in
group-reared
rats increased activity in the open arms and increased general activity
in the
elevated plus maze with no effect on water maze performance.
DSP-4-treated
isolates spent less time in the open arms and were hypoactive in the
plus maze
compared to group-reared DSP-4-treated rats, and had impaired retention
of
spatial memory in the water maze compared to isolate controls.
CONCLUSIONS:
DSP-4 treatment had an 'anxiolytic' effect in group-reared rats in the
elevated
plus maze. In the water maze, isolation rearing enhanced retention of
spatial
information, an effect normalised by NA depletion. The results
demonstrate the
importance of noradrenergic function in the regulation of
responsiveness to
environmental cues.
PMID: 11432687 [PubMed - indexed for MEDLINE]
162: Behav Brain Res. 2002 Feb 1;129(1-2):203-10.
Does head-only exposure to GSM-900 electromagnetic fields affect the
performance
of rats in spatial learning tasks?
Dubreuil D, Jay T, Edeline JM.
Laboratoire de Neurobiologie de l'Apprentissage, de la Memoire, et de la
Communication, CNRS-UMR 8620, bat. 446, Universite Paris Sud, Orsay,
France.
diane.dubreuil@ibaic.u-psud.fr
The rapid expansion of mobile communication has generated intense
interest, but
has also fuelled ongoing concerns. In both humans and animals,
radiofrequency
radiations are suspected to affect cognitive functions. More
specifically,
several studies performed in rodents have suggested that spatial
learning can be
impaired by electromagnetic field exposure. However, none of these
previous
studies have simulated the common conditions of GSM mobile phones use.
This
study is the first using a head-only exposure system emitting a 900-MHz
GSM
electromagnetic field (pulsed at 217 Hz). The two behavioural tasks
that were
evaluated here have been used previously to demonstrate performance
deficits in
spatial learning after electromagnetic field exposure: a classical
radial maze
elimination task and a spatial navigation task in an open-field arena
(dry-land
version of the Morris water maze). The performances of rats exposed for
45 min
to a 900-MHz electromagnetic field (1 and 3.5 W/kg) were compared to
those of
sham-exposed and cage-control rats. There were no differences among
exposed,
sham, and cage-control rats in the two spatial learning tasks. The
discussion
focuses on the potential reasons that led previous studies to conclude
that
learning deficits do occur after electromagnetic field exposure.
PMID: 11809512 [PubMed - indexed for MEDLINE]
163: Behav Brain Res. 2002 May 14;132(2):135-43.
Behavioral profile of rats submitted to session 1-session 2 in the
elevated
plus-maze during diurnal/nocturnal phases and under different
illumination
conditions.
Bertoglio LJ, Carobrez AP.
Departamento de Farmacologia, CCB, Universidade Federal de Santa
Catarina, Rua
Ferreira Lima 82, Florianopolis, SC 88015-420, Brazil.
The elevated plus-maze (EPM) model usually employs nocturnal species
(e.g. rats
and mice) and the tests are almost exclusively performed during the
diurnal
phase (lights on), leading some laboratories to perform experiments
with animals
under a reversed light cycle to overcome this problem. However, it is
questionable whether the artificial reversal of the light cycle for
short
periods guarantees modifications in all the physiological parameters
found in
normal subjects. The present study evaluated the session 1-session 2
(S1-S2) EPM
profile in rats during their normal diurnal or nocturnal phase using
different
illumination conditions. Prior exposure to the EPM decreased open arm
exploration for all groups in S2, regardless of the circadian phase and
illumination condition; however, this behavior was decreased in
subjects tested
during the nocturnal phase, when compared to the diurnal phase. Risk
assessment
(RA) behavior was decreased under high illumination for both circadian
phases in
S1 and increased in the first minute of S2, when compared to the last
minute of
S1. Although open arm exploration and RA behavior were decreased under
high
illumination, when compared to low illumination conditions in both
circadian
phases, general locomotor activity was only decreased during the
nocturnal
phase. The results are discussed in terms of circadian variations in the
behavioral profile and as a possible source of variability in
pre-clinical
models of anxiety.
PMID: 11997144 [PubMed - indexed for MEDLINE]
164: J Bone Joint Surg Am. 1994 Apr;76(4):489-501.
Low-power electromagnetic stimulation of osteotomized rabbit fibulae. A
randomized, blinded study.
The purpose of this study was to determine whether low-power-consuming
symmetrical-waveform electromagnetic stimuli could increase the
stiffness of
fracture sites in a rabbit fibular-osteotomy model. Both active and
placebo
devices were used in a blinded study protocol. Dose-response studies of
pulse
amplitude and pulse width were performed by continuous application
(twenty-four
hours a day) of repetitive (fifteen-hertz), bursted
(five-millisecond-long)
symmetrical, rectangular electromagnetic stimulus waveforms. The power
consumed
by these stimuli is approximately one-fifth that consumed by the pulsing
electromagnetic field devices that are in current clinical use.
Significant
increase of callus bending stiffness was produced by pulse widths of
five to
seven microseconds and pulse amplitudes of fifty to 100 millivolts.
Anxiolytic effects of aniracetam in three different mouse models of
anxiety and
the underlying mechanism.
Nakamura K, Kurasawa M.
CNS Supporting Laboratory, Nippon Roche Research Center, 200 Kajiwara,
Kamakura,
247-8530, Kanagawa, Japan. kazuo.nakmura@roche.com
The anxiolytic effects of aniracetam have not been proven in animals
despite its
clinical usefulness for post-stroke anxiety. This study, therefore,
aimed to
characterize the anxiolytic effects of aniracetam in different anxiety
models
using mice and to examine the mode of action. In a social interaction
test in
which all classes (serotonergic, cholinergic and dopaminergic) of
compounds were
effective, aniracetam (10-100 mg/kg) increased total social interaction
scores
(time and frequency), and the increase in the total social interaction
time
mainly reflected an increase in trunk sniffing and following. The
anxiolytic
effects were completely blocked by haloperidol and nearly completely by
mecamylamine or ketanserin, suggesting an involvement of nicotinic
acetylcholine, 5-HT2A and dopamine D2 receptors in the anxiolytic
mechanism.
Aniracetam also showed anti-anxiety effects in two other anxiety models
(elevated plus-maze and conditioned fear stress tests), whereas
diazepam as a
positive control was anxiolytic only in the elevated plus-maze and
social
interaction tests. The anxiolytic effects of aniracetam in each model
were
mimicked by different metabolites (i.e., p-anisic acid in the elevated
plus-maze
test) or specific combinations of metabolites. These results indicate
that
aniracetam possesses a wide range of anxiolytic properties, which may be
mediated by an interaction between cholinergic, dopaminergic and
serotonergic
systems. Thus, our findings suggest the potential usefulness of
aniracetam
against various types of anxiety-related disorders and social
failure/impairments.
PMID: 11412837 [PubMed - indexed for MEDLINE]
166: Vrach Delo. 1980 Oct;(10):103-9.
[Biomedical evaluation of electromagnetic fields]
[Article in Russian]
Serdiuk AM.
PMID: 7434689 [PubMed - indexed for MEDLINE]
167: Physiol Bohemoslov. 1981;30(2):149-55.
Contactless method for the continuous and selective study of motor
activity in
the laboratory rat.
Rech F.
The author suggests a system for the continuous, direct, long-term
recording of
the motor activity of a particular laboratory rat in a group. A pickup
of the
animal's presence and its motor activity in the given space supplies a
desired
signal coded by frequency modulation of the carrier frequency.
Detection is
effected by a phase lock. The carrier frequency of a controlled
oscillator is
altered within small limits by means of inductive coupling between the
tuning
coil of the oscillator and a shading ring. The shading ring, which
marks the
experimental animal, is oval and is made of thin insulated litz wire
sutured in
place subcutaneously on the animal's back. The coil of the controlled
oscillator
surrounds the whole of the space in which motor activity is recorded.
As an
example, in a study of maternal behaviour, the presence or absence of
the female
in the nest and the motor activity of the lactating female typical of
washing
the young and of suckling them are identified and compared with direct
observations.
PMID: 6454153 [PubMed - indexed for MEDLINE]
168: Biull Eksp Biol Med. 1976 Oct;82(10):1163-5.
[Changes in the selfexcitation reaction in rats under the effect of
modulated
electromagnetic field]
The effect of electromagnetic field with various modulation frequencies
(2, 7,
and 50 hertz) on the reaction of selfstimulation was studied in rats.
The
frequency of 2 hertz proved to cause a primary increase in the
incidence of the
selstimulation reaction, followed by its depression; the frequency 7
hertz at
first failed to alter the selfstimulation intensity and then led to the
gradual
reduction of the incidence of the selfstimulation reaction; the
frequency of 50
hertz depressed the selfstimulation reaction practically from the very
beginning. The changes in the selfstimulation reaction were independent
of the
localization of the stimulating electrodes, but were determined by the
frequency
of the EMF modulation.
[Prediction of the severity of damage and disruption of work ability in
reaction
of the body to alcohol load prior to radiation exposure in the
superlethal
range]
[Article in Russian]
Darenskaia NG, Korotkevich AO, Maliutina TS, Nasonova TA, Bulgakov AI.
State Research Center-Institute of Biophysics, Ministry of Health of
Russia,
Moscow, 123182 Russia.
In experiments on 121 white non-linear rats, 44 Papio hamadryas and 29
Macaca
fascicularis, animals' reactions on the alcohol impact (AI) and
following
exposure to supralethal doses were compared. The animals were
intravenously
injected with 5% ethanol in the glucose solution, 2.1 g/kg for rats and
0.46-0.51 g/kg for monkeys. Monkeys' response to AI was scored in
four-point
scale by estimating of abnormalities in motor activity, coordination of
motion
and changes in conditioned reflex activity. It was shown that changes
in the
ability of alcohol-injected rats to perform the learnt exercises in the
"jump
box" could be used for prediction of their response to the exposure to
supralethal doses of ionizing radiation. Observing the AI-response in
monkeys
along with a method "function of spying for moving object" made
possible to
predict not only a general degree of loss of working ability but also to
estimate individual impairments of spying functions. In 65% monkeys high
similarity of the reactions to AI and ionizing radiation was observed.
PMID: 12125263 [PubMed - indexed for MEDLINE]
170: Physiol Behav. 2001 Jan;72(1-2):99-106.
Influence of circadian phase and test illumination on pre-clinical
models of
anxiety.
Jones N, King SM.
Department of Psychology, University College London, Gower Street,
London WC1E
6BT, UK. nick@psychol.ucl.ac.uk
Pre-clinical models of anxiety, particularly the elevated plus-maze
(EPM), have
been shown to be sensitive to a variety of methodological variations.
Recent
research has implicated circadian phase of testing in influencing the
behavioural profile of 5-HT(1A) ligands on the EPM. The present study
investigated the effects of testing animals during the dark and light
phases and
in light and subjective dark test conditions on baseline behaviour in
animal
models of anxiety. Eighty singly housed male Sprague-Dawley rats were
exposed to
a battery of unconditioned, exploratory tests (EPM, open field arena,
holeboard)
and a new model of extreme anxiety, the unstable elevated exposed
plus-maze
(UEEPM). Circadian phase of testing failed to consistently alter
behaviour on
any model. Level of test illumination had no effect on subjects'
response to the
open field arena, holeboard or UEEPM. Dark testing increased locomotor
activity
on the EPM (total arm entries, closed arm entries and distance moved)
without
decreasing open-arm avoidance. The construct of anxiety as measured by
a number
of different paradigms withstood major intra-laboratory manipulation of
circadian phase of testing and illumination of apparatus. It is
suggested that
the effects of circadian rhythmicity may be confined to the behavioural
profiles
of serotonergic, particularly 5-HT(1A), ligands on the EPM.
PMID: 11239986 [PubMed - indexed for MEDLINE]
171: Brain Res. 2001 Jun 1;902(2):135-42.
Antagonism of CRF(2) receptors produces anxiolytic behavior in animal
models of
anxiety.
Takahashi LK, Ho SP, Livanov V, Graciani N, Arneric SP.
Department of Psychology, University of Hawaii, 96822, Honolulu, HI,
USA.
lkt@hawaii.edu
Two pharmacologically distinct CRF receptors are distributed in
different brain
regions and peripheral tissues. Studies suggest that CRF(1) receptors
play an
important role in mediating the anxiety provoking effects of CRF. In
contrast,
far less functional information is available on CRF(2) receptors.
Therefore, we
conducted dose response studies using antisauvagine-30 (anti-SVG-30,
0-20
microg, 20-min pretreatment, i.c.v.), a potent CRF(2) peptide
antagonist, and
tested rats in three models of anxiety - the conditioned freezing, the
elevated
plus maze, and the defensive-withdrawal test. Anti-SVG-30 produced a
significant
dose-dependent reduction in conditioned freezing. In the elevated plus
maze
test, administration of anti-SVG-30 effectively increased the number of
entries
and time spent in the open arms. In the defensive-withdrawal test,
anti-SVG-30
treatment facilitated exploratory activity in a large illuminated open
field.
Thus, in all three animal models, administration of anti-SVG-30 was
consistent
in producing an anxiolytic-like behavioral effect. In addition, a dose
of
anti-SVG-30 (10 microg) that produced anxiolytic-like behavior had no
significant effects on locomotor activity measured in an automated
activity box.
This latter finding suggests that antagonism of CRF(2) receptors is not
associated with a non-specific increase in behavioral movements. These
results
provide evidence that, in addition to CRF(1) receptors, CRF(2)
receptors may
play an important role in the mediation of anxiety behavior.
Anxiolytic effects of mecamylamine in two animal models of anxiety.
Newman MB, Manresa JJ, Sanberg PR, Shytle RD.
Center for Aging and Brain Repair, Department of Neurosurgery,
University of
South Florida College of Medicine, Tampa 33612, USA.
Clinical and preclinical evidence suggests that mecamylamine, a
nicotinic
receptor antagonist, may have anxiolytic properties. The purpose of
this study
was to further investigate the anxiolytic properties of mecamylamine in
rats as
measured by the Elevated Plus Maze and the Social Interaction models of
anxiety
and to determine if manipulation of the testing environment (either
brightly lit
or dimly lit conditions) influenced the results. Results indicated that
mecamylamine had significant anxiolytic effects in both the Elevated
Plus Maze
and Social Interaction Tests and that these effects were dependent on
dose
administered and the level of anxiety produced under different testing
conditions. If confirmed by further clinical research, nicotinic
receptor
antagonists like mecamylamine may represent a novel class of
anxiolytics.
PMID: 11866248 [PubMed - indexed for MEDLINE]
173: Zh Vyssh Nerv Deiat Im I P Pavlova. 2000 Nov-Dec;50(6):991-8.
[Characteristics of behavior of knockout mice with genetic monoamine
oxidase A
deficiency]
[Article in Russian]
Popova NK, Skrinskaia IuA, Amstislavskaia TG, Vishnivetskaia GB, Seif
I, De
Mayer E.
Institute of Cytology and Genetics, Russian Academy of Sciences,
Siberian
Branch, Novosibirsk.
The effect of deletion of monoamine oxidase A (MAO A) in the gene
encoding on
behavior of transgenic Tg8 mice was studied. A decrease in the
amplitude of
acoustic startle reflex rather than the prepulse inhibition was found
in lacking
MAO A Tg8 mice, as compared with the control C3H strain. The exploratory
activity in the hole-board test in Tg8 was decreased as well as the
number of
crossed lines in the light-dark test. Tg8 mice showed decreased latency
and
increased intensity of intermale aggression. At the same time, no
difference was
found between Tg8 and C3H mice in locomotor activity, in the expression
of
sexual motivation, and in the behavior in the elevated plus-maze test.
No
predisposition to catalepsy was shown.
PMID: 11190099 [PubMed - indexed for MEDLINE]
174: Gig Sanit. 1989 Oct;(10):80-1.
[Changes in enzyme activity of the lymphocytes in animals in the
evaluation of
the adaptive reactions to electromagnetic fields of industrial
frequency]
[Article in Russian]
Dyshlovoi VD, Ianovskaia AS, Chaplinskaia TS.
PMID: 2599412 [PubMed - indexed for MEDLINE]
175: Behav Brain Res. 2002 Apr 15;132(1):85-93.
Estrogen's effects on activity, anxiety, and fear in two mouse strains.
Morgan MA, Pfaff DW.
Laboratory of Neurobiology and Behavior, The Rockefeller University,
1230 York
Avenue, Box 275, New York, NY 10021, USA.
Estrogen has effects on activity levels and emotional reactivity in
both humans
and rats. In a recent study conducted in ovariectomized (OVX) C57BL/6
(C57) mice
we found that treatment with estradiol benzoate (EB) increased anxiety,
fear
learning, and running wheel activity relative to vehicle control (Veh).
The
present study was conducted to examine the stability of these findings
across
mouse strains (C57 and Swiss-Webster; SW), to get a better sense of the
magnitude of the anxiety response by reducing baseline anxiety levels,
and to
discover if EB affects activity levels in a safe environment other than
the
home-cage running wheel. Mice of both strains treated with EB (s.c.
implant, 25
microg in sesame oil, which enters the body over 5 weeks) were more
anxious than
Veh animals in the open field, elevated plus, and dark-light transition
tests.
SW animals were less anxious than C57 in the elevated plus. EB-treated
animals
of both strains were more active in the running wheel than Veh animals,
and more
active in the test of spontaneous activity in the home cage.
EB-treatment also
increased fear learning in a step-down avoidance task. EB appears to
have a
consistent but moderate effect in elevating anxiety and in increasing
fear
learning in two strains of mice. It is also involved in increasing
activity in
two different types of locomotion in the safer home cage. We conclude
that these
results of increased anxiety/fear and increased activity are suggestive
of a
general increase in arousal, with both sets of responses increasing the
likelihood of reproductive behaviors occurring only when the environment
predicts success.
PMID: 11853861 [PubMed - indexed for MEDLINE]
176: Med Pregl. 2001 Mar-Apr;54(3-4):119-27.
Morphophysiological status of rat thyroid gland after subchronic
exposure to low
frequency electromagnetic field.
[Article in English, Croatian]
Rajkovic V, Matavulj M, Lukac T, Gledic D, Babic L, Lazetic B.
Institut za biologiju, Prirodno-matematicki fakultet, 21000 Novi Sad.
vesnar@unsim.ns.ac.yu
The objective of this study was to examine the impact of low-frequency
electromagnetic field on male rat thyroid gland of Mill Hill strain.
Animals
were exposed to 50 Hz frequency, of decaying intensity from 500 microT
to 50
microT and 10 V/m field, beginning 24 hours after birth, 7 hours a day,
5 days a
week during three months. Results of histological and stereological
analysis
showed increased volume density of thyroid follicles, decreased
thickness of the
follicular epithelium, intrafollicular colloid content in lumen,
decreased
thyroid activation index, increased volume density of parafollicular
cells,
decreased volume of interfollicular connective tissue and increased
number of
degranulated mast cells in exposed animals in regard to control animals.
Radioimmunologic assays were used to examine thyroid hormone
concentrations in
the blood serum revealing decrease of the total T4 as well as of total
T3 in
animals exposed to electromagnetic field in regard to controls. The
obtained
results show that a three month-exposition of animals to low frequency
electromagnetic field led to morphofunctional alterations of the
thyroid gland
that can be referred to as reduced activity of the gland.
PMID: 11759202 [PubMed - indexed for MEDLINE]
177: J Microw Power. 1976 Jun;11(2):145-6.
Proceedings: Comparative study of the action of three types of
microwave fields
upon the behavior of the white rat.
[Changes in the immune status under the influence of high-frequency
electromagnetic radiation]
[Article in Russian]
Dumanskii IuD, Nogachevskaia SI.
Experiments on white rats showed that electromagnetic radiation (24
MHz, 400 W/m
and 20 W/m) caused leucopenia, reduction of E and EAC rosette formation
of
lymphocytes, functional activity of neutrophils within 2 months of
radiation. No
immunosuppressive effect was seen with 24 MHz, 100 W/m radiation, while
400 W/m
inhibited E-rosette formation in the presence of tissue antigens.
PMID: 8379142 [PubMed - indexed for MEDLINE]
179: Neuropsychobiology. 2001;43(3):192-9.
Dopaminergic lateralisation in the forebrain: relations to behavioural
asymmetries and anxiety in male Wistar rats.
Thiel CM, Schwarting RK.
Institute of Physiological Psychology I, Heinrich-Heine-University of
Dusseldorf, Germany.
Neurochemical lateralisation has been demonstrated in dopaminergic
systems in
the rat brain, and it has been suggested that such lateralisation might
contribute to asymmetric and emotional behaviour. Here, we investigated
dopaminergic brain lateralisation in relation to spontaneous and
drug-induced
behavioural asymmetries, and to emotional behaviour in a sample of 24
male
Wistar rats. Asymmetric behaviour was measured in the open field in the
undrugged state and after a systemic challenge with the muscarinic
receptor
antagonist scopolamine (0.5 mg/kg). Emotional behaviour was measured in
the
elevated plus-maze. Dopaminergic lateralisation was assessed by means
of a
post-mortem analysis of tissue dopamine (DA) and dihydroxyphenyl acetic
acid
(DOPAC) content. We found higher DOPAC/DA ratios in the neostriatum,
ventral
striatum, frontal cortex and amygdala of the right hemisphere. In the
open
field, the complete sample of rats did not show a left/right asymmetry
in
spontaneous behaviour, whereas systemic scopolamine induced a left-sided
preference in thigmotactic scanning. A correlational analysis yielded
individual
relationships between behaviour and post-mortem neurochemistry, since
lateralisation of DOPAC/DA ratios in favour of the right ventral
striatum was
related to right-side thigmotaxis. Furthermore, a right dopaminergic
lateralisation in the frontal cortex was associated with lower anxiety.
The
study indicates that asymmetries in ventral striatal dopamine might
contribute
to side preferences in thigmotactic scanning while frontal dopaminergic
lateralisation might influence emotional processing. Copyright 2001 S.
Karger
AG, Basel
PMID: 11287799 [PubMed - indexed for MEDLINE]
180: Pharmacol Res. 2001 Oct;44(4):329-35.
Baclofen prevents hypoxia-induced consolidation impairment for passive
avoidance
in rats.
Car H, Oksztel R, Nadlewska A, Wisniewski K.
Medical Academy of Bialystok, Department of Pharmacology, Mickiewicza
2c, 15-222
Bialystok, Poland.
We investigated the effects of baclofen, a selective GABA-B receptor
agonist, on
certain behaviours in rats after short-term hypoxia, as a model of
experimentally induced amnesia. Baclofen given intraperitoneally (i.p.)
in a
dose of 0.25 mg kg(-1) increased the number of crossings and bar
approaches in
the open field, but was ineffective in the passive avoidance tests; it
also
shortened the time spent in open arms and reduced the number of open
arms
entries in an elevated 'plus' maze, being a measure of anxiety. Hypoxia
(2% O2,
98% N2) within 4 min profoundly impaired locomotor activity,
consolidation and
retrieval of conditioned responses, and exhibited a proaxiogenic effect
in the
elevated 'plus' maze in rats--it reduced the time spent in open arms
and the
number of entries to closed and open arms. Baclofen's effect on
locomotor and
exploratory activity was substantially impaired after hypoxia, i.e. rats
exhibited a significant reduction in those activities. This agonist of
GABA-B
receptor used before hypoxia significantly improved consolidation, but
had no
effect on retrieval. In the elevated 'plus' maze rats pre-treated with
baclofen
and then subjected to hypoxia prolonged the time spent in open arms,
reduced the
time spent in closed arms, and increased the number of entries to the
arms, i.e.
exhibited anxiolytic effect. We conclude, therefore, that baclofen
improved
consolidation of passive avoidance in rats undergoing hypoxia.
Copyright 2001
Academic Press.
PMID: 11592869 [PubMed - indexed for MEDLINE]
181: Physiol Behav. 2002 Feb 1-15;75(1-2):15-23.
Spatial memory deficit and emotional abnormality in OLETF rats.
Li XL, Aou S, Hori T, Oomura Y.
Department of Integrative Physiology, Graduate School of Medical
Sciences,
Kyushu University 60, Fukuoka 812-8582, Japan.
Cholecystokinin (CCK) is deeply involved in the control of learning and
emotional behaviors. The authors characterize the behavioral properties
of
Otsuka Long Evans Tokushima Fatty (OLETF) rats, which lack the CCK-A
receptor
because of a genetic abnormality. In the Morris water-maze task, the
OLETF rats
showed an impaired spatial memory. In the inhibitory avoidance test,
they showed
facilitating response 24 h after training. Hypoalgesia was observed in a
hot-plate test. In the elevated plus-maze and food neophobia test,
OLETF rats
showed an anxiety-like response. In addition, OLETF rats were
hypoactive in the
Morris water-maze and the elevated plus-maze. The results suggest that
the OLETF
rats showed a spatial memory deficit, hypoactivity and anxiety due, at
least in
part, to the lack of CCK-A receptors.
PMID: 11890948 [PubMed - indexed for MEDLINE]
182: Neuropeptides. 2001 Apr;35(2):100-9.
The effects of CRA 1000, a non-peptide antagonist of
corticotropin-releasing
factor receptor type 1, on adaptive behaviour in the rat.
Harro J, Tonissaar M, Eller M.
Department of Psychology, University of Tartu, Estonia. jharro@ut.ee
Intracerebrally administered CRF has been demonstrated to elicit several
behavioural deficits in novel and potentially stressful experimental
paradigms,
and to promote activity in familiar situations. This study examined the
effect
of CRA 1000, a novel non-peptide antagonist of CRF(1)receptors, on rat
behaviour
in tests of anxiolytic and antidepressant activity and novelty-oriented
behaviour. CRA 1000 (1.25-10 mg/kg) had no major effect in elevated
plus-maze
and social interaction tests. However, CRA 1000 (5 mg/kg) significantly
reduced
immobility in the forced swimming test, suggesting an
antidepressant-like
effect. In the exploration box test, CRA 1000 (1.25 mg/kg) had an
anxiolytic
effect on rat exploratory behaviour both in intact rats and after
lesioning of
the projections of locus coeruleus by DSP-4 (50 mg/kg) treatment. A
higher dose
of CRA 1000 (5 mg/kg) tended to have anxiolytic-like effects in DSP-4
pretreated
rats, but in intact animals this dose prevented the increase in
exploration
which develops with repeated exposure to initially anxiety-provoking
situations.
Taken together, these experiments demonstrate that CRF1 receptor
blockade by CRA
1000 has antidepressant-like effects, does not have a robust
anti-anxiety effect
in non-stressed animals, but does have anxiolytic-like effects in more
complex
tasks, which can be observed also after denervation of the locus
coeruleus
projections. However, large doses of CRF1 receptor antagonists may
reduce
motivation of exploratory behaviour in familiar environments. Copyright
2001
Harcourt Publishers Ltd.
PMID: 11384205 [PubMed - indexed for MEDLINE]
183: In Vivo. 2001 Nov-Dec;15(6):489-94.
In vivo modulation of ETS genes induced by electromagnetic fields.
Mucci N, Ianni A, Ursini CL, Arzani D, Bhat NK, Navarra P, Romano-Spica
V.
Department of Occupational Medicine, I.S.P.E.S.L., Rome, Italy.
We have previously shown that electromagnetic field (EMF) exposure
induces ETS1
oncogene overexpression in different cell lines. In order to
investigate in vivo
EMF effects, BALB/c mice were exposed at different times to 50 MHz
radiation,
modulated (80%) at 16 Hz. The exposed and control animals were
sacrificed and
the spleen excised for rt-pcr and western blot analysis. We observed an
increase
in ETS1 mRNA and protein expression, but a decrease in ETS2 protein
levels.
Preliminary results from this experimental model show in vivo evidence
of the
effect of EMF on ETS oncogene expression.
PMID: 11887334 [PubMed - indexed for MEDLINE]
184: Toxicol Pathol. 1999 May-Jun;27(3):286.
Comment on:
Toxicol Pathol. 1999 May-Jun;27(3):267-78.
Toxicol Pathol. 1999
May-Jun;27(3):279-85.
Rodent carcinogenicity studies on magnetic fields.
Schwetz B.
FDA (HF-32), Rockville, Maryland 20857, USA.
Publication Types:
Comment
PMID: 10356704 [PubMed - indexed for MEDLINE]
185: Exp Neurol. 2001 May;169(1):96-104.
Enhanced excitability induced by ionizing radiation in the kindled rat.
Jenrow KA, Ratkewicz AE, Elisevich KV.
Epilepsy Research Laboratory, Henry Ford Health Sciences Center,
Detroit,
Michigan, 48202, USA.
Evidence derived from both clinical and experimental investigations has
suggested an influence of ionizing radiation on focal epileptogenicity.
To
better characterize this influence we applied focal ionizing radiation
to a
kindled epileptic focus in the rat amygdala. The right and left
basolateral
amygdala and right frontal cortex were implanted with concentric bipolar
electrodes. Rats were kindled through a minimum of 10 stage 5 seizures
by
afterdischarge-threshold electrostimulation of the left amygdala, after
which
generalized seizure thresholds were determined prior to irradiation.
The left
amygdala was exposed to single-fraction central-axis doses of either 18
or 25 Gy
using a beam-collimated (60)Co source (1.25 MeV). Generalized seizure
thresholds
were then redetermined at weekly intervals for 10 weeks and at monthly
intervals
for an additional 3 months. We observed no significant changes in
seizure
threshold during the postirradiation interval; however, we did observe
persistent changes in seizure dynamics manifesting within the first week
postirradiation. These consisted of an increased tendency for seizure
activity
to propagate into brain stem circuits during the primary ictus (i.e.,
"running
fits") and an increased tendency for secondary convulsions to emerge
postictally. These effects involving seizure dynamics have not been
reported
previously and appear to represent a radiation-induced disinhibition of
one or
more neural circuits. The disparity between these effects and earlier
reports of
seizure-suppressive effects resulting from analogous radiation
exposures is
discussed in relation to kindling and status epilepticus-induced
pathogenesis
within the hippocampus. Copyright 2001 Academic Press.
PMID: 11312562 [PubMed - indexed for MEDLINE]
186: Acta Physiol Pol. 1975 Sep-Oct;26(5):523-7.
Changes in the pharmacodynamics and pharmacokinetics of psycholeptic
drugs in
radiation-sickness. Effect of x-ray radiation on pharmacodynamic
activity of
nitrazepam in animals.
Szczawinska K, Chodera A, Wojciak Z, Kozaryn I.
PMID: 1224989 [PubMed - indexed for MEDLINE]
187: Pol Merkuriusz Lek. 2001 Nov;11(65):447-51.
[Immunotropic effects of electromagnetic fields in the range of radio-
and
microwave frequencies]
[Article in Polish]
Dabrowski MP, Stankiewicz W, Sobiczewska E, Szmigielski S.
Zaklad Ochrony Mikrofalowej Wojskowego Instytutu Higieny i
Epidemiologii w
Warszawie.
On the grounds of reviewed literature and the results of own
experiments, the
authors present current views on the possible immunotropic influence of
low
energy electromagnetic fields, in the range of radio- and microwave
frequencies.
They conclude, that a more systematic and multidisciplinary
investigations
should be undertaken, comprising the wide spectrum of immune
homeostatic tasks,
including defensive, immunoregulatory and pro-regenerative capabilities
of
immune system exposed to rapid environmental spread of different
electromagnetic
emitters.
[The dependence of the biological effect of electron radiation on the
pulse
repetition rate. The dependence of mortality and life span in rats on
the
radiation dose and pulse repetition rate]
[Article in Russian]
Darenskaia NG, Nasonova TA, Aleshin SN, Vainer EA, Grinev MP.
Quantitative regularities have been established for mortality and
life-span of
rats in relation to the pulse recurrence frequency (3-2400 s-1) of
electron
radiation with electron energies of 25 and 50 MeV. Electrons with pulse
recurrence frequencies of 600 and 1200 s-1 have shown a higher
biological
effectiveness.
PMID: 9244519 [PubMed - indexed for MEDLINE]
189: Diabetes Obes Metab. 1999 Sep;1(5):281-4.
Intracerebroventricularly administered corticotropin-releasing factor
inhibits
food intake and produces anxiety-like behaviour at very low doses in
mice.
Momose K, Inui A, Asakawa A, Ueno N, Nakajima M, Fujimiya M, Kasuga M.
Metabolic Disease Research, Pharmacology Laboratories, Institute for
Drug
Discovery Research, Yamanouchi Pharmaceutical Co. Ltd, Tsukuba, Japan.
AIM: Previous studies have demonstrated that corticotropin-releasing
factor
(CRF) produces behavioural, physiological and immunological responses
similar to
those induced by stress. However, these findings have been validated
largely in
laboratory rats. METHODS: We examined the effects of
intracerebroventricular
(i.c.v.) administration of CRF on anxiety and food intake in mice.
Using the
elevated-plus maze, we measured anxiety levels after i.c.v. CRF in
mice. We also
measured food intake for 2 h after i.c.v. CRF. RESULTS: CRF increased
the normal
preference for the closed arms of the maze at a very low dose of 3 pmol,
indicating an anxiogenic effect. CRF powerfully suppressed food intake
at the
doses of 3-300 pmol for over 2 h. CONCLUSION: Our results demonstrate
that
i.c.v. CRF evokes anxiogenic behaviour and suppresses feeding with the
same
dose-response relationships in mice. CRF may thus play a role in
integrating the
overall responses to stress through co-ordinated actions in the brain
of this
species.
PMID: 11225639 [PubMed - indexed for MEDLINE]
190: Biofizika. 1999 Sep-Oct;44(5):931-2.
[Change in the percent of lactate dehydrogenase isoenzyme level in
testes of
animals exposed to superhigh frequency radiation]
[Article in Russian]
Afromeev VI, Tkachenko VN.
Research Production Venture Stek, Tula, Russia.
The content of six lactate dehydrogenase isoenzymes in testes of rats
exposed to
electromagnetic field of 3-cm wavelength range was studied. The changes
in their
percent contents were found to be inhomogeneous compared with control.
It is
assumed that electromagnetic radiation affects the organs of the human
urinogenital system. The results can be used for estimating the safety
of
persons professionally exposed to electromagnetic radiation of the
industrial
frequency range and in the therapy of diseases of the urinogenital
system.
PMID: 10624539 [PubMed - indexed for MEDLINE]
191: Arh Hig Rada Toksikol. 1999 Mar;50(1):5-11.
Animal study on electromagnetic field biological potency.
Trosic I, Matausicpisl M, Radalj Z, Prlic I.
Institute for Medical Research and Occupational Health, Zagreb, Croatia.
itrosic@imi.hr
This recent basic research study used an animal model protocol to assess
specific biomarkers of the effect of non-ionising, non-thermal
radiation (2450
MHz microwave radiation at 5-15 mW/cm2) on bone marrow, peripheral
blood, and
bronchoalveolar free cell populations. Of 40 male Wistar rats taken in
the
study, 20 animals of the experimental group were irradiated for 2 hours
a day, 5
days a week, and subsequently killed on days 1, 8, 16, and 30 of the
experiment.
The remaining 20 rats served as control. All animals were previously
intratracheally instilled with biologically inert microspheres to see
the
influence of irradiation on lung retention kinetics. The cell response
to chosen
electromagnetic irradiation was followed quantitatively and
qualitatively using
the standard laboratory methods. The results of peripheral blood cell
response
suggested a decreasing tendency in total leukocyte count and in relative
lymphocyte count in the treated group. A slight increase was also
observed in
granulocyte count and in the absolute count of peripheral blood
erythrocytes
over control animals.
Do rats show a behavioral sensitivity to low-level magnetic fields?
Stern S.
Department of Environmental Medicine, School of Medicine and Dentistry,
University of Rochester, New York 14642, USA.
PMID: 8554636 [PubMed - indexed for MEDLINE]
193: Bioelectromagnetics. 2002 Jan;23(1):68-82.
Health and safety implications of exposure to electromagnetic fields in
the
frequency range 300 Hz to 10 MHz.
Litvak E, Foster KR, Repacholi MH.
World Health Organization, Geneva, Switzerland.
An international seminar on health effects of exposure to
electromagnetic fields
(EMF) in the frequency range from 300 Hz to 10 MHz (referred to as the
Intermediate Frequency (IF) range) was held in Maastricht, Netherlands,
on 7-8
June 1999. The seminar, organized under the International EMF Project,
was
sponsored jointly by the World Health Organization (WHO), the
International
Commission on Non-Ionizing Radiation Protection (ICNIRP), and the
Government of
the Netherlands. This report does not attempt to summarize all of the
material
presented at the conference, but focuses on sources of exposure,
biophysical and
dosimetric considerations pertinent to extrapolating biological data
from other
frequency ranges to IF and identifies potential health concerns and
needs for
developing exposure guidelines. This paper is based on presentations at
the
conference and reports of working groups consisting of the speakers and
other
experts. It concludes with recommendations for further research aimed at
improving health risk assessments in this frequency range. Copyright
2002
Wiley-Liss, Inc.
Publication Types:
Congresses
PMID: 11793407 [PubMed - indexed for MEDLINE]
194: Eur J Cell Biol. 2001 Aug;80(8):562-6.
Stimulation of phagocytosis and free radical production in murine
macrophages by
50 Hz electromagnetic fields.
Simko M, Droste S, Kriehuber R, Weiss DG.
University of Rostock, Institute of Cell Biology and Biosystems
Technology,
Division of Environmental Physiology, Germany.
myrtill.simko@biologie.uni-rostock.de
Effects of 50 Hz electromagnetic fields on phagocytosis and free radical
production were examined in mouse bone marrow-derived macrophages.
Macrophages
were in vitro exposed to electromagnetic fields using different
magnetic field
densities (0.5-1.5 mT). Short-time exposure (45 min) to electromagnetic
fields
resulted in significantly increased phagocytic uptake (36.3% +/- 15.1%)
as
quantified by measuring the internalization rate of latex beads.
Stimulation
with 1 nM 12-0-tetradecanoylphorbol-13-acetate (TPA) showed the same
increased
phagocytic activity as 1 mT electromagnetic fields. However,
co-exposure to
electromagnetic fields and TPA showed no further increase of bead
uptake, and
therefore we concluded that because of the absence of additive effects,
the
electromagnetic fields-induced stimulation of mouse bone marrow-derived
macrophages does not involve the protein kinase C signal transduction
pathway.
Furthermore, a significant increased superoxide production after
exposure to
electromagnetic fields was detected.
[Effects of 2375 MHz pulse-modulated microwave radiation on ATPase
activity of
the rat muscle actomyosin]
[Article in Russian]
Pashovskina MS, Akoev IG.
Solution of rat muscle actomyosin (AM) was exposed to pulse-modulated
microwave.
Carried frequency was 2375 MHz. The rectangular pulse modulation was in
the
range of 50-300 pulses per second. It was shown that AM activity was
dependent
both on modulation frequency as well as on microwave intensity. It was
shown the
frequencies of modulation which were changed ATP-ase activity of AM.
Weak, pulsing electromagnetic fields can modify biological processes.
The
hypothesis that responses to such induced currents depend on pulse
characteristics was evaluated by using transcription as the target
process. Two
pulses in clinical use, the repetitive single pulse and the repetitive
pulse
train, were tested. These pulses produced different results from each
other and
from controls when transcription in dipteran salivary gland cells was
monitored
with tritiated uridine in transcription autoradiography, cytological
nick
translation, and analysis of isolated RNA fractions. The single pulse
increased
the specific activity of messenger RNA after 15 and 45 minutes of
exposure. The
pulse train increased specific activity only after 45 minutes of
exposure.
PMID: 6857248 [PubMed - indexed for MEDLINE]
197: Farmakol Toksikol. 1980 Jul-Aug;43(4):334-8.
[Pharmacological characteristics of the tranquilizing action of
hydiphen]
[Article in Russian]
Zainkonnikova IV, Val'dman AV, Kozlovskaia MM, Rzhevskaia GF.
Hydiphen--hydrazide of diphenylphosphinylacetic acid--is a new Soviet
tranquilizer having an original spectrum of psychotropic activity. It
depresses
an aroused emotional state of fear-anxiety, decreases the state of
conflict in
group interaction. It produces neither myorelaxation nor increase in
positive
emotions. The drug is not toxic. It possesses the central
N-cholinolytic,
antiadrenergic and antiserotonin effects.
PMID: 7439361 [PubMed - indexed for MEDLINE]
198: Bioelectromagnetics. 2002 Jan;23(1):2-6.
Effect of short duration electromagnetic field exposures on rat mass.
School of Physical Education, West Virginia University, Morgantown, West
Virginia 26506, USA. msandrey@wvu.edu
Daily preexposure and postexposure mass measurements of 65 rats (young
males and
females, old males) a proprietary pulsed wound healing field, pulsed
electromagnetic field, (PEMF), or their control fields for 4 h/day for
21 days.
Statistical analysis of mass changes over time showed that young rats
exposed to
PEMF lost more mass and recovered it more slowly compared to controls
(2-4% more
loss) than did older PEMF exposed rats or any 60 Hz exposed rats. We
conclude
that daily preexposure and postexposure mass measurements are needed to
adequately assess the effects of electromagnetic fields on body mass.
Copyright
2002 Wiley-Liss, Inc.
PMID: 11793400 [PubMed - indexed for MEDLINE]
199: Med Tr Prom Ekol. 2000;(5):8-11.
[Changes in gastric electric activity and serum catecholamine level
under the
influence of electromagnetic microwaves (experimental studies)]
[Article in Russian]
Kulkybaev GA, Pospelov NI.
Chronic experiments on 17 dogs revealed that ultrahigh-frequency
electromagnetic
waves applied on epigastric area and head induce a double-phase
response:
depressed electric activity of gaster and increased total
catecholamines level
during exposure, but higher gastric activity and lower levels of
epinephrine and
norepinephrine in 24 hours after each of 10 procedures and during 7
days after
10 procedures. Double-phase changes in electric activity of gaster
could be
explained by double-phase fluctuations of humoral division in
chromaffin system.
PMID: 10881538 [PubMed - indexed for MEDLINE]
200: Behav Brain Res. 2001 Aug 1;122(2):169-74.
Vibrissal sense is not the main sensory modality in rat exploratory
behavior in
the elevated plus-maze.
Cardenas F, Lamprea MR, Morato S.
Faculdade de Filosofia Ciencias e Letras de Ribeirao Preto,
Universidade de Sao
Paulo, Av. Bandeirantes 3900, Ribeirao Preto-SP 14040-901, Brazil.
Four groups of male Wistar rats were submitted to acute bilateral
removal of
mystacial vibrissae at different lengths from the follicle. Each group
was
divided into two subgroups, tested under high (150 Lux) and low
environmental
illumination (2 Lux). All the subjects were allowed to freely explore an
elevated plus-maze for 5 min. Results indicated that rats tested under
low
illumination tended to explore the open arms more frequently and longer
then
rats tested under high illumination. When tested under low
illumination, rats in
the group that suffered whole vibrissa removal stayed longer in the
open arms
than those in the other groups but did not differ in the number of
entries. The
average increase in the length of open arm entries, rather than a
decrease in
aversion to the open arms, may be due to the need of more time to obtain
information about the environment since there is no light and the
vibrissae were
removed. This effect was not seen with rats tested under high
illumination,
possibly because vision could be used to obtain relevant information.
PMID: 11334647 [PubMed - indexed for MEDLINE]
201: Biofizika. 1995 Sep-Oct;40(5):969-73.
[Modification of reactions of rats to the effect of weak variable
magnetic
fields using a stress factor]
[Article in Russian]
Temur'iants NA, Mikhailov AV, Malygina VI.
Stress-factor (hypokinesia) modifies the reaction of the adaptation,
which
develops under the changeable magnetic fields influence with 8 Hz
frequency and
5 microT induction. It's being corroborated by the decrease of
nonspecific
resistance in the initial adaptation period, by the increase of central
nervous
system excitability, by the absence of catecholamines accumulation in
the
hypothalamus and in adrenal glands.
PMID: 8555295 [PubMed - indexed for MEDLINE]
202: Med Tr Prom Ekol. 1995;(7):40-2.
[A neuropharmacological study of amnesia in animals induced by ultra
high
frequency electromagnetic irradiation]
[Article in Russian]
Iasnetsov VV, Pal'tsev IuP, Popov VM, Levina AV.
PMID: 7551702 [PubMed - indexed for MEDLINE]
203: Pol J Pharmacol. 2000 Jul-Aug;52(4):247-54.
3,5-DHPG influences behavioral effects of baclofen in rats.
Car H, Nadlewska A, Wisniewski K.
Department of Pharmacology, Medical Academy, Bialystok, Poland.
The role of 3,5-DHPG, an agonist of group I metabotropic glutamate
receptors (I
mGluRs) in certain behavioral effects of baclofen, an agonist of GABA-B
receptor, was assessed. Baclofen, given intraperitoneally (ip) at the
dose of
0.25 mg/kg, enhanced the number of crossings and bar approaches in the
open
field and was ineffective in the passive avoidance tests, and it
prolonged time
spent in closed arms and shortened time spent in open arms, reduced
number of
entries into open arms in the elevated "plus" maze, measuring anxiety.
3,5-DHPG
given intracerebroventricularly (icv) alone at doses of 0.01, 0.1 and
1.0 nmole
did not change locomotor activity in the open field test, except bar
approaches:
when 3,5-DHPG was given at the dose of 0.01 nmole it enhanced the
activity of
rats. At doses of 0.01 and 1.0 nmole it improved, but at the dose of
0.1 nmole
it significantly impaired retrieval in the passive avoidance situation.
All used
doses of 3,5-DHPG did not influence the time spent in closed or open
arms and
the number of entries into open or closed arms in the elevated "plus"
maze.
3,5-DHPG, given at the doses of 0.01, 0.1 and 1.0 nmole 10 min after
baclofen
significantly changed the effect of baclofen decreasing crossings and
rearings
in the open field, while 3,5-DHPG used at the doses of 0.01 and 1.0
nmole in
rats pretreated with baclofen reduced bar approaches. Rats which
received
baclofen and, 10 min later, 3,5-DHPG at doses of 0.1 and 1.0 nmole,
showed
significantly improved retrieval in the passive avoidance response. The
effect
of 3,5-DHPG and baclofen were changed, i.e. 3,5-DHPG and baclofen can
cooperate
in retrieval process. Coadministration of baclofen and 3,5-DHPG at the
dose of
1.0 nmole reduced time spent in the open arms in comparison with
baclofen, i.e.
this dose of 3,5-DHPG changed the effect of baclofen evaluated in the
"plus"
maze. Summary, the activation of I mGluR by 3,5-DHPG modulates GABA-B
neurotransmission stimulated by baclofen, which is reflected by changing
behavioral activity of rats.
PMID: 11345480 [PubMed - indexed for MEDLINE]
204: Biofizika. 1994 May-Jun;39(3):515-8.
[Controlled effect of an impulse electromagnetic field on the central
nervous
system]
[Article in Russian]
Pestriaev VA.
Faint influences of impulses (1 ms) electromagnetic fields (173 A/m)
with
dynamic frequency-impulse modulation, which is regulated by feedback
from
electrocorticogram, and influences with fixed frequency of impulses run
infra-low range affect on changing of current function state of central
nervous
system in different ways, is established. The white rats in the
sleep-wake cycle
were used in experiments. Besides, the first regimen of influence is
more
effective for changing of character of bioelectrical activity of cortex
of head
brain. The second one-for support of current processes of
synchronization.
PMID: 8043642 [PubMed - indexed for MEDLINE]
205: Eur J Pharmacol. 2001 Dec 14;433(1):91-9.
Increased anxiety and impaired memory in rats 3 months after
administration of
3,4-methylenedioxymethamphetamine ("ecstasy").
Morley KC, Gallate JE, Hunt GE, Mallet PE, McGregor IS.
Department of Psychology, University of Sydney, Sydney, NSW 2006,
Australia.
Male Wistar rats were administered either (a) a high dose regime of
3,4-methylenedioxymethamphetamine (MDMA) (4 x 5 mg/kg, i.p. over 4 h on
each of
2 consecutive days), (b) a moderate dose regime of MDMA (1 x 5 mg/kg on
each of
2 consecutive days), (c) D-amphetamine (4 x 1 mg/kg over 4 h on each of
2 days),
or (d) vehicle injections. The high MDMA dose regime and the amphetamine
treatment both produced acute hyperactivity and hyperthermia. Twelve
weeks
later, all rats were tested in the drug-free state on a battery of
anxiety tests
(elevated plus maze, emergence and social interaction tests). A further
2 weeks
later they were tested on a novel object recognition memory task. Rats
previously given the neurotoxic dose of MDMA showed greater anxiety-like
behaviour on all three anxiety tests relative to both controls and
D-amphetamine-treated rats. Rats given the moderate MDMA dose regime
also showed
increased anxiety-like behaviour on all three tests, although to a
lesser extent
than rats in the high dose group. In the object recognition task, rats
given the
high MDMA dose regime showed impaired memory relative to all other
groups when
tested at a 15-min delay but not at a 60-min delay. Rats previously
exposed to
amphetamine did not differ from saline controls in the anxiety or
memory tests.
These data suggest that moderate to heavy MDMA exposure over 48 h may
lead to
increased anxiety and memory impairment 3 months later, possibly
through a
neurotoxic effect on brain serotonin systems.
The effect of melatonin on morphological changes in liver induced by
magnetic
field exposure in rats.
Gokcimen A, Ozguner F, Karaoz E, Ozen S, Aydin G.
Department of Histology and Embryology, S. Demirel University, School of
Medicine, Isparta, Turkey. agokcimen@yahoo.com
In this study, we aimed to investigate the possible effect of melatonin
on
morphological changes in liver induced by magnetic fields exposure.
Thirty
albino young male Wistar Albino rats were used in the study. They were
divided
into 3 groups. Control group (C) (n: 10) received daily intraperitoneal
injections of saline (0.1 ml/100 g) containing 5% ethanol for two
weeks. Only
magnetic field exposed (MF) group (n: 10); only magnetic field exposed
had daily
intraperitoneal injections of physiologic saline (0.1 ml/100 g)
containing 5%
ethanol for two weeks. Magnetic field exposed and melatonin treated
(MF+m) group
(n: 10); melatonin was dissolved in ethanol with further dilution in
physiological saline. The animals in this group were exposed magnetic
fields for
two weeks. The magnetic fields exposed animals had intraperitoneal
single dose
of 4 mg/kg melatonin (0.1 ml/100 g) at 10:00 o'clock daily for two weeks
following magnetic fields exposure. We used commercial CB handheld
portable
transceiver, Midland (USA) labelled, of 4 Watts, 40 channel. This
channel
frequency has been measured 27.17 MHz with frequency counter. According
to the
IRPA exposure standards; for 27 MHz, for 6 min, exposure limit is 0.2
mW/cm2.
This value is for General Public. For occupational exposure limit is 1
mW/cm2.
We have to consider General Public exposure limit. Therefore our limit
is 0.2
mW/cm2. In other words; in this study; our exposure is always over the
recommended limit. All the animals were decapitated. Liver samples were
fixed in
buffered neutral formalin. Paraffin sections were dyed with
hematoxylen-eosin.
Sections were examined under light microscopy. In MF group; sinusoidal
dilatations, mixed cell infiltrations noticed in the periportal area,
necrosis
and vacuoler degeneration were determined in liver samples. However,
parenchymal
and stromal structures were observed to be prevented partially from
effects of
magnetic fields in melatonin treated group. In conclusion, it is
suggested that
melatonin has a mild preventive effect on magnetic field exposed
changes in
liver tissue in the rats.
[Grooming and motor activity of rats during hyperbaric exposure]
[Article in Russian]
Sledkov AIu.
An experiment was performed in which Wistar male rats were exposed to a
N2-O2
atmosphere at 10 kgf/sm2 or He-O2 atmosphere at 10 and 40 kgf/cm2.
During the
experiment grooming and motor activity as well as plasma corticosterone
were
investigated. Irrespective of the atmosphere composition, behavioural
and
biochemical parameters were found to increase significantly. At 10
kgf/cm2, the
grooming frequency returned to normal faster than at a higher pressure.
These
observations give evidence for a nonspecific effect of the above
hyperbaric
factors on the parameters taken under study.
PMID: 8577160 [PubMed - indexed for MEDLINE]
209: Med Pregl. 1997 Sep-Oct;50(9-10):357-62.
[The effect of low-frequency electromagnetic fields on the
neuroendocrine
system]
[Article in Croatian]
Lazetic B, Kozarcic T, Stankov K.
Zavod za fiziologiju, Medicinski fakultet, Novi Sad.
This paper presents literature data about effects of low-intensity
variable
electromagnetic fields on the neuroendocrine system of experimental
animals. We
mostly paid attention to electromagnetic fields frequently found in our
environment, in technological processes, even in our everyday life.
This study
shows that the regulatory systems (nervous and endocrine) are extremely
sensitive to effects of electromagnetic fields. In regard to structures
of the
central nervous system hypothalamus shows particularly high sensitivity
whereas
we can consider a hypothesis that effects of this physical factor may be
expected in other systems too. It has been emphasized that the effects
of
electromagnetic fields on regulatory mechanisms may be connected with
primary
disturbances on the cellular and subcellular (mitochondrial) level.
Publication Types:
Review
Review, Academic
PMID: 9471530 [PubMed - indexed for MEDLINE]
210: Vestn Ross Akad Med Nauk. 1998;(8):27-32.
[Induction of long-term depression (with anxiety and fear components) by
immunization of rats against pargyline]
The active immunization of albino rats against pargyline (a MAO B
inhibitor)
induced the formation of antibody to pargyline and results in deep
depressive
changes and fear. These changes were observed within 6 weeks after the
first
immunization. Therefore, it opens the possibility to model depression
long by
exerting the minimum influences. There was also a long-term modulation
of
craving for alcohol.
Effects of subchronic methylphenidate hydrochloride administration on
the
locomotor and exploratory behavior of prepubertal mice.
Carrey N, McFadyen MP, Brown RE.
Department of Outpatient Psychiatry, IWK-Grace Hospital, Halifax, Nova
Scotia,
Canada. ncarrey@iwkgrace.ns.ca
The increasing use of methylphenidate hydrochloride (MPH) in children
led us to
examine the effects of MPH administration in developing mice. Male CD-1
mice
were administered MPH (40 mg/kg, subcutaneously) or saline daily from
postnatal
days 26-32. The mice were then tested from postnatal days 33-37 for
locomotion
and exploration in the open field, anxiety in the elevated plus maze,
and
learning in the Morris water maze. The results indicate that
MPH-pretreated mice
were more exploratory and less fearful in the open field, entering more
center
squares than saline controls. MPH-pretreated mice also exhibited less
anxiety,
spending more time in the open arm and exhibiting more head dips in the
elevated
plus maze than controls. There was no significant difference between
MPH and
saline-treated mice in the time taken to find the visible or hidden
platform in
the water maze task. The results indicate that treatment with MPH has
significant effects on later behavior, reducing fear and anxiety, and
increasing
exploration, but no effect on performance in a spatial learning task.
PMID: 11191688 [PubMed - indexed for MEDLINE]
212: Biofizika. 2001 Jul-Aug;46(4):753-60.
[Effect of extremely high frequency electromagnetic radiation of low
intensity
on parameters of humoral immunity in healthy mice]
[Article in Russian]
Lushnikov KV, Gapeev AB, Sadovnikov VB, Cheremis NK.
Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino,
Moscow
Region, 142290 Russia.
The modification of indices of the humoral immune response to
thymus-dependent
antigen (sheep erythrocytes) after a whole-body exposure of healthy
mice to
low-intensity extremely-high-frequency electromagnetic radiation was
studied.
Male NMRI mice were exposed in the far-field zone of horn antenna at a
frequency
of 42.0 GHz and energy flux density of 0.15 mW/cm2 under different
regimes: once
for 20 min, for 20 min daily during 5 and 20 successive days before
immunization, and for 20 min daily during 5 successive days after
immunization
throughout the development of the humoral immune response. The
intensity of the
humoral immune response was estimated on day 5 after immunization by
the number
of antibody-forming cells of the spleen and antibody titers. Changes in
cellularity of the spleen, thymus and red bone marrow were also
assessed. The
indices of humoral immunity and cellularity of lymphoid organs changed
insignificantly after acute exposure and series of 5 exposures before
and after
immunization of the animals. However, after repeated exposures for 20
days
before immunization, a statistically significant reduction of thymic
cellularity
by 17.5% (p < 0.05) and a decrease in cellularity of the spleen by
14.5% (p <
0.05) were revealed. The results show that low-intensity
extremely-high-frequency electromagnetic radiation with the frequency
and energy
flux density used does not influence the humoral immune response
intensity in
healthy mice but influences immunogenesis under multiple repeated
exposures.
PMID: 11558390 [PubMed - indexed for MEDLINE]
213: Biofizika. 2001 Nov-Dec;46(6):1096-102.
[Degranulation of skin mast cells caused by high frequency
electromagnetic
irradiation of low intensity]
Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino,
Moscow
Region, 142290 Russia.
It was shown by light and electron microscopy that local exposure of the
projection of the MC-8 lao-gun acupuncture point in rat pad to
low-intensity
(0.05 mW/cm2) extremely high-frequency (42.0 GHz) electromagnetic
radiation
caused a degranulation of derma mast cells. It was suggested that the
response
of skin mast cells is an important amplifying mechanism in the chain of
events
leading to a systemic response of the organism to low-intensity
electromagnetic
radiation.
PMID: 11771285 [PubMed - indexed for MEDLINE]
214: Gig Sanit. 1981 Oct;(10):35-8.
[Effect of a superhigh-frequency electromagnetic field on animals of
different
ages]
[Article in Russian]
Shutenko OI, Koziarin IP, Shvaiko II.
PMID: 7308758 [PubMed - indexed for MEDLINE]
215: Gig Sanit. 1990 Aug;(8):62-3.
[Hygienic standardization of electromagnetic radiation from two-channel
meteorological radar stations]
[Article in Russian]
Nikitina NG, Tomashevskaia LA.
The study was designed to analyze the impact of the combined
electromagnetic
fields (EMF) with the wavelength of 10 and 0.8 cm and various levels of
energy
current density on the central nervous system, metabolic processes,
immune
resistance and reproductive function. Proceeding from the obtained data
maximum
allowable levels of EMF produced by the prospective two-channel
meteorological++
radars were established.
Institute of Experimental Medicine, Hungarian Academy of Science, P.O.
Box 67,
1450 Budapest, Hungary. haller@koki.hu
RATIONALE: The serotonergic system and the
hypothalamus-hypophysis-adrenocortical axis reciprocally influence each
other.
Therefore, the interaction between stress and serotonergic anxiolytics
should be
of major concern for both laboratory investigations and clinical
treatment.
OBJECTIVES: We have studied the effects of the serotonergic anxiolytic
buspirone
in rats in which basal levels of glucocorticoids were low and stable,
while
acute stress reactions were inhibited or exogenously induced. METHODS:
Rats were
adrenalectomised. Subcutaneous corticosterone pellets maintained basal
glucocorticoid concentrations while acute changes were mimicked by
corticosterone injections. Anxiety was assessed by the social
interaction test.
Temporal changes were evaluated by submitting rats to the same
manipulations
three times at two-day intervals. RESULTS: Buspirone applied to animals
with
stable and low plasma glucocorticoid concentrations induced a dramatic
increase
in social interactions. A slight locomotor suppressive effect was also
noticed.
The effects of buspirone proved to be stable over time in these
animals. Acute
treatment with corticosterone doubled the locomotor suppressive effects
of
buspirone and reversed its anxiolytic effects: the
buspirone-corticosterone
combination was anxiogenic after the first application. During the
second and
third treatment, the impact of corticosterone on buspirone efficacy
gradually
decreased, but the combined treatment remained about half as effective
in
reducing anxiety as buspirone alone.
PMID: 11605098 [PubMed - indexed for MEDLINE]
217: Brain Res Mol Brain Res. 2001 Aug 15;92(1-2):78-84.
Altered emotional behavior in PACAP-type-I-receptor-deficient mice.
Otto C, Martin M, Wolfer DP, Lipp HP, Maldonado R, Schutz G.
Division Molecular Biology of the Cell, German Cancer Research Center,
Im
Neuenheimer Feld 280, 69120 Heidelberg, Germany.
PAC1 (pituitary adenylate cyclase activating polypeptide type I
receptor) is a
G-protein-coupled receptor that binds the strongly conserved
neuropeptide PACAP
(pituitary adenylate cyclase activating polypeptide) with a
thousandfold higher
affinity than the related peptide VIP (vasoactive intestinal peptide).
PAC1
shows strong expression in brain areas which have been implicated in the
emotional control of behavior, such as the amygdala, the hypothalamus,
the locus
coeruleus and the periaqueductal gray. To assess whether PAC1-mediated
signaling
has an impact on emotional behavior, we analysed two different mutant
mouse
lines with an ubiquitous or a forebrain-specific inactivation of PAC1
in several
testing paradigms modelling general locomotor activity and
anxiety-related
behavior. We clearly demonstrate that mice with a ubiquitous but not
with a
forebrain-specific deletion of PAC1 exhibit elevated locomotor activity
and
strongly reduced anxiety-like behavior. We could not observe any gross
alteration in circadian rhythmicity nor any enhanced sensitivity
towards ethanol
in the mutant mice. We previously demonstrated that PAC1 plays a
crucial role in
contextual fear conditioning. Therefore the finding that PAC1-deficient
mice
exhibit reduced anxiety is quite exciting, since the receptor and hence
its
ligand PACAP seem to be important for both, innate and learned fear.
[Role of polarization and resonance in assessing the biological effects
of
electromagnetic radiation]
[Article in Russian]
Galkin AA.
The dosimetric concept of measurements of electromagnetic radiations
(EMR)
during irradiation of biological objects can be realized by methods of
mathematical modelling of EMR interactions with biological objects,
which can be
represented as an image of the human body as a uniform ellipsoid of
revolution.
The efficient surface of EMR absorption for the models shows a marked
resonance
dependence on the radiation frequency. The ratio of the largest to the
smallest
axes of the ellipsoid of revolution can be used as a resonance
criterion.
Besides, radiation polarization needs to be taken into consideration.
This paper
discusses the frequency dependence of the efficient absorption surface
for three
major types of radiation polarization. The paper demonstrates an
applicability
of the calculation method to the evaluation of the EMR absorbed dose
rate.
PMID: 7070047 [PubMed - indexed for MEDLINE]
219: Brain Res. 2002 Jul 5;943(1):142-50.
Human urocortin II: mild locomotor suppressive and delayed
anxiolytic-like
effects of a novel corticotropin-releasing factor related peptide.
Department of Neuropharmacology, CVN7, The Scripps Research Institute,
La Jolla,
CA 92037, USA. gvaldez@scripps.edu
Recently, human urocortin II (hUcn II), a member of the
corticotropin-releasing
factor (CRF) peptide family, was identified. The following experiments
sought to
compare the effects of this novel CRF-related peptide versus those of
ovine CRF
(oCRF) on locomotor activation and anxiety-related behavior, using the
locomotor
activity test and the elevated plus maze, respectively. To examine
locomotor
activity during the active (dark) and inactive (light) phases, rats were
intracerebroventricularly (i.c.v.) injected with 0, 0.1, 1.0 or 10
microg of
hUcn II (n=8/group active; n=6-9/group inactive) or oCRF (n=8/group
active;
n=8/group inactive) 2 h after the onset of their respective testing
phase and
monitored for 3 (inactive) or 5 (active) h. To compare the effects of
CRF-related peptides on exploration of the elevated plus maze, rats were
pretreated (i.c.v. 0, 0.1, 1.0 or 10 microg) with hUcn II
(n=7-11/group) or oCRF
(n=7-10/group), 10 min prior to testing. Delayed effects in the
elevated plus
maze were examined in rats injected with 1.0 microg of hUcn II
(n=8/group) or
oCRF (n=6-8/group), or vehicle (n=8/group) 1, 4 or 6 h before testing.
In
contrast to the activational effects of oCRF, hUcn II mildly suppressed
locomotor activity during the inactive phase. hUcn II did not acutely
affect
open arm exploration in the elevated plus maze, whereas oCRF decreased
this
measure. However, hUcn II increased open arm exploration 4 h after
injection.
Thus, hUcn II exhibits mild motor suppressive effects and delayed
anxiolytic-like effects, suggesting a time-dependent role for hUcn II
in the
regulation of stress-related behavior.
PMID: 12088848 [PubMed - indexed for MEDLINE]
220: Zh Vyssh Nerv Deiat Im I P Pavlova. 2001 Nov-Dec;51(6):733-42.
[Behavioral analysis of consequences of chronic blockade of NMDA-type
glutamate
receptors in the early postnatal period in rats]
[Article in Russian]
Latysheva NV, Raevskii KS.
Research Institute of Pharmacology, Russian Academy of Medical
Sciences, Moscow.
In view of the hypothesis that glutamatergic dysfunction of brain can
underlie
the negative symptoms of schizophrenia (including cognitive deficit),
the aim of
this study was to develop a model of cognitive impairment in Wistar
male rats
after administration of a noncompetitive NMDA-receptor antagonist in
early
postnatal period. Rat pups were daily subcutaneously injected with 0.05
mg/kg
MK-801 on postnatal days 7-49. On the 27th and 28th days 24 h after the
last
previous injection, the MK-801-treated rats demonstrated lower
spontaneous
locomotor and exploratory activity in comparison with saline control,
however,
they retained the reaction of hyperlocomotion which developed
immediately after
the MK-801 administration. In these rats, the anxiety level in the
elevated
plus-maze (on the 40th postnatal day) was found to be decreased, and
the spatial
learning in food rewarded task was negatively affected (on the
50th-54th days).
It is suggested that impairment of the input of sensory information and
its
correct assessment by the animals can be associated with the early
neonatal
blockade of NMDA glutamate receptors.
PMID: 11871038 [PubMed - indexed for MEDLINE]
221: J Neuroendocrinol. 2002 Jul;14(7):549-54.
Hormonal and behavioural responses of paradoxical sleep-deprived rats
to the
elevated plus maze.
Suchecki D, Tiba PA, Tufik S.
Department of Psychobiology, Universidade Federal de Sao Paulo, Escola
Paulista
de Medicina, Sao Paulo, Brazil. suchecki@psicobio.epm.br
Activation of the hypothalamic-pituitary-adrenal (HPA) axis is observed
immediately after 96 h of paradoxical sleep (PS) deprivation. However,
when
individually or group PS-deprived rats are challenged with a mild
stressor, they
exhibit a facilitation of the corticosterone response, and a faster
return to
basal levels than control rats. Because the housing condition
influences coping
behaviour, we tested whether the type of PS deprivation (individually
or in
group) influenced anxiety-like behaviour in the elevated plus-maze and
the
accompanying adrenocorticotropin (ACTH) and corticosterone responses.
Individually (I-DEP) or group deprived (G-DEP) rats and their
appropriate
control groups were either killed immediately after 96 h of sleep
deprivation
(time-point 0 or 'basal') or exposed to a 5-min test on the elevated
plus maze
and sampled 5, 20 or 60 min after test onset. Control of I-DEP rats
showed
reduced locomotor activity and augmented anxiety-like behaviour,
replicating the
effects of social isolation. Although I-DEP rats exhibited higher motor
activity
than cage control rats, these groups did not differ in regard to the
percentage
of entry and time spent in the open arms. G-DEP rats, in turn,
ambulated more,
entered and remained longer in the open arms, exhibiting less
anxiety-like
behaviour. PS-deprived rats exhibited higher ACTH and corticosterone
'basal'
secretion than control rats. For all groups, peak ACTH secretion was
reached at
the 5-min time-point, returning to unstressed basal levels 60 min after
the
test, except for G-DEP rats, which showed a return at 20 min. Peak
levels of
corticosterone occurred at 5 min for PS-deprived groups and at 20 min
for
control groups. G-DEP rats showed a return to 'basal' unstressed levels
at 20
min, whereas the I-DEP and control groups did so at 60 min. A negative
correlation between exploration in the open arms and hormone
concentrations was
observed. These data indicate that housing condition influences the
subsequent
behaviour of PS-deprived rats in the EPM which, in turn, seems to
determine the
secretion profile of ACTH and corticosterone in response to the test.
[Recovery processes in the cerebral cortex, myocardium and thymus of
rats with
experimental atherosclerosis exposed to low-frequency electromagnetic
fields on
the head]
Studies of animals with experimental sclerosis has shown that a course
of 10
procedures of alternative magnetic field (AMF) (50 Hz, 30 mT, 3 min
daily)
promotes partial recovery of the lipid spectrum and corrects
vasomotor-metabolic
disturbances in the cerebral cortex, myocardium and thymus caused by
atherosclerosis. Combination of AMF with constant magnetic field in the
same
regime and location does not produce a hypolipidemic effect in
atherosclerotic
animals and this, in combination with increased vascular permeability
may
aggravate the condition. Activated microcirculation, antioxidant and
antiproteinase effects in activation of biosynthetic processes in the
cerebral
cortex reflect inhibition in the CNS in this combined effect and create
conditions for a hypotensive effect.
[Role of modulation in biological effects of electromagnetic radiation]
[Article in Russian]
Grigor'ev IuG.
Data, describing a role of modulation of electromagnetic fields in
development
of biological effect, are considered. Outcomes of researches,
indicating the
dependence of a response of nervous and immune systems on a kind of
modulation
at low levels of effect, are represented. The necessity of the account
of a role
of modulation in an evaluation of electromagnetic danger is formulated.
PMID: 9019276 [PubMed - indexed for MEDLINE]
224: Zh Vyssh Nerv Deiat Im I P Pavlova. 2001 Sep-Oct;51(5):563-71.
[Dynamics of spectral characteristics of theta- and alpha-range EEG
during
negative emotional reactions]
[Article in Russian]
Il'iuchenok IR, Savost'ianov AN, Valeev RG.
Institute of Higher Nerous Activity and Neurophysiology, Russian
Academy of
Sciences, Moscow.
Power characteristics of the EEG theta and alpha rhythms were studied
in a human
in neutral state and during a conditioned negative emotional reaction
(Fp1, Fp2,
F3, F4, C3, C4, P3, P4, O1, O2, F7, F8, T3, T4, T5, and T6
derivations). A
significant increase in the relative spectral power in the narrow theta
band of
7.4-8.1 Hz in the frontocentral and temporal brain regions was observed
during
the development of the negative emotional reaction. The alpha-rhythm
dynamics
during the negative reaction was substantially individual and could be
expressed
in either an increase, or decrease in relative spectral power of
different
alpha-frequencies. No pronounced changes in their dynamics could also be
observed. In some subjects the spectral power of the medium-frequency
alpha-rhythm significantly decreased, that of the high-frequency rhythm
increased, and changes in the spectral power of the low-frequency alpha
range
varied.
PMID: 11764515 [PubMed - indexed for MEDLINE]
225: Behav Brain Res. 2002 Apr 1;131(1-2):67-78.
Amygdala or ventral hippocampal lesions at two early stages of life
differentially affect open field behaviour later in life; an animal
model of
neurodevelopmental psychopathological disorders.
Daenen EW, Wolterink G, Gerrits MA, Van Ree JM.
Department of Pharmacology, Division of Pharmacology and Anatomy Rudolf
Magnus
Institute for Neurosciences, University Medical Center Utrecht, PO Box
85060,
3508, AB, Utrecht, The Netherlands.
Psychiatric disorders like schizophrenia or autism are thought to
result from
disruption of the normal pattern of brain development. Abnormalities in
the
amygdaloid complex and hippocampus have been reported in these
disorders. In the
present study rats were lesioned in the amygdala or ventral hippocampus
on day 7
of life (immature brain) or day 21 of life (almost mature brain) and
open field
behaviour was determined later in life before and after puberty.
Lesioning on
day 7 resulted in behavioural changes, interpreted as locomotor
stereotypy and
decreased anxiety in case of amygdala or hippocampus, respectively.
These
effects were more profoundly present after puberty. Lesioning on day 21
did not
result in these behavioural changes, which subscribes to the importance
of the
stage of brain maturation on functional development. The results
suggest that
the behavioural changes in rats lesioned on day 7 may due to a
malfunctioning of
structures connected to the amygdala or ventral hippocampus. Brain
lesions made
on day 7 of life may serve as a potential model of psychopathological
neurodevelopmental disorders.
PMID: 11844573 [PubMed - indexed for MEDLINE]
226: Bioelectromagnetics. 2001 Apr;22(3):212-5.
GSM phone signal does not produce subjective symptoms.
Koivisto M, Haarala C, Krause CM, Revonsuo A, Laine M, Hamalainen H.
Centre for Cognitive Neuroscience, University of Turku, Finland.
mika.koivisto@utu.fi
The influence of pulsed radiofrequency (RF) electromagnetic fields of
digital
GSM mobile phones (902 MHz, 217 Hz pulse modulation) on subjective
symptoms or
sensations in healthy subjects were studied in two single-blind
experiments. The
duration of the RF exposure was about 60 min in Experiment 1 and 30 min
in
Experiment 2. Each subject rated symptoms or sensations in the
beginning of the
experimental session and at the end of both the exposure and the
nonexposure
conditions. The symptoms rated were headache, dizziness, fatigue,
itching or
tingling of the skin, redness on the skin, and sensations of warmth on
the skin.
The results did not reveal any differences between exposure and
non-exposure
conditions, suggesting that a 30-60 min exposure to this RF field does
not
produce subjective symptoms in humans. Copyright 2001 Wiley-Liss, Inc.
PMID: 11255218 [PubMed - indexed for MEDLINE]
227: Med Tr Prom Ekol. 1999;(12):9-13.
[Role of nonspecific cellular resistance factors in hygienic evaluation
of
electromagnetic nonionizing radiation]
[Article in Russian]
Obukhan EI.
The most sensitive indices of the blood system at EMF exposure
(disorders of
megakaryocytes differentiation, unspecific reactions, repopulation of
the blasts
cells a. al.) have been determined by the cytologic investigations. At
has been
revealed that allowable UVF levels effect are situated below the
threshold of
activisation of adaptive reactions (less than 0.01 mV/cm2), for
occupational
conditions--at the level of compensatory processes (0.05-0.1 mV/cm2).
The
intensities higher than 0.5 mV/cm2 were estimated as critical.
Involution of
megakaryocytes, polimorphism and disturbances the structure of
leucocytes a. al.
were revealed as EMF markers which allow to carry out an
express-diagnostic.
PMID: 11965742 [PubMed - indexed for MEDLINE]
228: J Psychopharmacol. 2001 Jun;15(2):76-82.
Interactions between LY354740, a group II metabotropic agonist and the
GABA(A)-benzodiazepine receptor complex in the rat elevated plus-maze.
Ferris P, Seward E, Dawson GR.
Merck Sharp and Dohme Research Laboratories, Neuroscience Research
Centre,
Harlow, Essex, UK.
Flumazenil, a benzodiazepine (BZ) receptor antagonist, and naloxone, a
non-selective mu-receptor antagonist, were used to investigate whether
the
anxiolytic action of LY354740
[1S,2S,5R,6S-2-aminobicyclo[3.1.0]hexane-2,6-dicarboxylate
monohydrate], a Group
II metabotropic glutamate receptor agonist, was mediated through the
benzodiazepine binding site on the GABA(A) receptor and opioid pathways.
LY354740 (1.0-10.0 mg/kg i.p.) induced dose-dependent anxiolytic-like
effects in
the rat elevated plus-maze. The anxiolytic-like effects of LY354740
(10.0 mg/kg)
and the benzodiazepine receptor agonist, chlordiazepoxide (CDP, 5.0
mg/kg i.p.)
were blocked by flumazenil (15.0 mg/kg i.p.). By contrast, naloxone
(10.0 mg/kg
i.p.) failed to affect the anxiolytic-like effects of either LY354740
or CDP.
The behaviour of animals treated with flumazenil or naloxone alone did
not
significantly differ from that of animals treated with vehicle alone.
This study
suggests that the anxiolytic-like effects of LY354740 on the elevated
plus-maze
may be directly or indirectly mediated by the benzodiazepine binding
site on the
GABA(A) receptor complex.
8-OH-DPAT, but not deramciclane, antagonizes the anxiogenic-like action
of
paroxetine in an elevated plus-maze.
Koks S, Beljajev S, Koovit I, Abramov U, Bourin M, Vasar E.
Department of Physiology, University of Tartu, Estonia. Sulev.Koks@ut.ee
OBJECTIVE: To investigate whether a 5-hydroxytryptamine (5-HT) reuptake
inhibitor (paroxetine) has an anxiogenic-like effect and what possible
pharmacological mechanism underlies that action. METHODS: We used the
rat
elevated plus-maze paradigm followed by measurement of locomotor
activity. Some
of the rats were subjected to handling and adaptation to the
experimental
situation, while the rest were naive to the test situation. Paroxetine
was
administered as a single treatment and in combination with the 5-HT1A
receptor
agonist (8-OH-DPAT) or 5-HT2A/2C receptor antagonist (deramciclane).
RESULTS:
The administration of paroxetine induced an anxiogenic-like action in
rats
adapted to handling, but not in handling naive animals. Treatment with
paroxetine (0.1-2 mg/kg) reduced the number of open arm visits and time
spent in
open arms, and the ratio between open and total arm entries in the
elevated
plus-maze. Paroxetine also decreased the number of line crossings and
head-dips.
Paroxetine caused the strongest anti-exploratory action at a dose of
0.5 mg/kg.
Paroxetine did not suppress the locomotor activity of rats, showing
that the
described anti-exploratory effect was behaviourally specific to the
plus-maze.
Pretreatment with 8-OH-DPAT (0.05 mg/kg) completely reversed the
anxiogenic-like
action of paroxetine, whereas treatment with deramciclane (2 mg/kg)
affected
only the number of closed arm visits. Deramciclane (0.5-2 mg/kg) and
8-OH-DPAT
(0.01-0.1 mg/kg) changed neither exploratory behaviour nor locomotor
activity if
given as single treatments to the habituated rats. CONCLUSION: The 5-HT
reuptake
inhibitor, paroxetine, at a low dose (0.5 mg/kg) induces an
anxiogenic-like
action in handling adapted rats. The effectiveness of 8-OH-DPAT against
paroxetine probably supports a role of both pre- and postsynaptic
5HT-ergic
mechanisms in the anxiogenic-like action of paroxetine.
[Enzymatic activity of some tissues and blood serum from animals and
humans
exposed to microwaves and hypothesis on the possible role of free
radical
processes in the nonlinear effects and modification of emotional
behavior of
animals]
Institute of Cell Biophysics, Russian Academy of Science, Pushchino,
142290
Russia. admin@icb.psn.ru
The dependence of activities of actomyosin ATPase, alkaline phosphatase,
aspartataminotranspherase, monoaminoxidase and that of affective rat
behavior on
frequency of modulation of microwaves (0.8-10 microW/cm2) was explored
at
short-time actions. Series of nonlinear phenomenons, inexplicable from
positions
of the energy approaches are revealed, The working hypothesis explaining
opportunity of high performance of weak and super-weak microwaves and
other
revealed phenomena by resonance interaction of such electromagnetic
radiofrequency radiation with paramagnetic molecules of biological
tissues was
proposed. This resonance interaction activate free radicals and initiate
auto-supporting and auto-intensifying of chain chemical reactions. The
spontaneous autocatalytic oxidation of catecholamines enlarges a common
pool of
free radicals, capable to participate in such enhanced generating. The
protective role of monoaminoxidase is postulated. Monoaminoxidase is
basically
located on an outer surface of mitochondrias and it is deaminating
monoamines.
The deaminating prevents penetration of catecholamines inside of
mitochondrias
and their quinoid oxidation there with formation of free-radical
semi-quinons,
capable to destroy system of ATP synthesis. These inferences are
obliquely
confirmed by the experimentally revealed correlation between activity of
monoaminoxidase and integrative activity of the rat brain.
Neuron activity in the prefrontal cortex of the brain in rats with
different
typological characteristics in conditions of emotional stimulation.
Zaichenko MI, Mikhailova NG, Raigorodskii YuV.
Institute of Higher Nervous Activity and Neurophysiology, Russian
Academy of
Sciences, Moscow.
Male Wistar rats were separated according to the "emotional resonance"
method
(groups of animals avoiding ("altruists") and not avoiding ("egotists")
the pain
cries of partner rats) and neuron activity in the prefrontal areas of
the cortex
was studied in the right and left hemispheres. Assessments were made of
changes
in the frequency of nerve cell spike activity (in relation to the
baseline
activity of neurons in sated animals) in rats subjected to one day of
food
deprivation and after electrical stimulation of emotionally positive
(lateral
hypothalamus) and negative (tegmentum of the midbrain) brain structures
and
after exposure to the pain cries of partner rats. The results of these
experiments revealed a series of differences in the cell activities of
the two
groups of rats. In conditions of hunger, the discharge frequency in the
"altruists" was higher than that in "egotists." Cortical neuron
responses to
positive stimulation were greater than those to negative stimulation in
rats of
both groups. Intracerebral stimulation produced significantly greater
increases
in discharge frequency in neurons of both prefrontal areas of the
cortex in
"altruists" than in "egotists." In both groups of rats, neurons in the
right
hemisphere responded to emotionally negative stimulation with
significantly
greater activation than cells in the left hemisphere, while activity in
the left
hemisphere was greater in conditions of emotionally positive
stimulation.
"Altruists" showed significantly greater neuron responses during
exposure to
pain cries from "victim" rats in both the right and left hemispheres.
The
responses of "egotists" to "victim" cries were not significantly
different from
baseline activity levels.
PMID: 11430574 [PubMed - indexed for MEDLINE]
232: Eur J Pharmacol. 2001 Aug 3;425(1):43-50.
Effect of chronic administration of flesinoxan and fluvoxamine on
freezing
behavior induced by conditioned fear.
Li XB, Inoue T, Hashimoto S, Koyama T.
Department of Psychiatry, Hokkaido University Graduate School of
Medicine, North
15, West 7, Kita-ku, Sapporo, 060-8638, Japan. xiao@med.hokudai.ac.jp
The present study investigated the acute effects of flesinoxan (a
selective
5-HT(1A) receptor agonist), fluvoxamine (a selective serotonin reuptake
inhibitor) and their co-administration on the expression of conditioned
freezing, and index of anxiety in rats. This study also examined the
acute
effects of fluvoxamine and flesinoxan following chronic flesinoxan or
chronic
fluvoxamine on the expression of conditioned freezing. Acute
administration of
flesinoxan (s.c.; 0.1-3 mg/kg) reduced freezing dose dependently, and
fluvoxamine (i.p.) at a high dose (60 mg/kg) reduced freezing
significantly.
Acute co-administration of fluvoxamine (30 mg/kg) and flesinoxan (0.3
mg/kg)
showed an additive inhibitory effect on freezing. Chronic flesinoxan
treatment
(0.3 mg/kg, for 13 days) did not affect the inhibitory effect of acute
flesinoxan treatment, but enhanced that of acute fluvoxamine (30 mg/kg)
on
conditioned freezing. Chronic fluvoxamine treatment (30 mg/kg, for 13
days)
enhanced the inhibitory effect of acute fluvoxamine (30 mg/kg) and the
inhibitory effect of acute flesinoxan (0.3 mg/kg) on conditioned
freezing. These
results suggest that co-administration of a selective serotonin reuptake
inhibitor and a 5-HT(1A) receptor agonist is useful for the treatment
of anxiety
disorders.
PMID: 11672573 [PubMed - indexed for MEDLINE]
233: Ross Fiziol Zh Im I M Sechenova. 2000 Aug;86(8):979-86.
[Changes in the animal behavior caused by sequential changes of
dominants
related to reproduction]
[Article in Russian]
Vinogradova EP.
St. Petersburg State University, Russia.
Female rats during the sex dominanta (proestrus) revealed lower anxiety
scores
and a higher general level of activity than the rats in diestrus.
Responses to
stress were also more obvious in proestrus. During gestation the rats
revealed a
lower activity and a higher anxiety. In lactation, the rats' behaviour
was
similar to that in proestrus.
PMID: 11059015 [PubMed - indexed for MEDLINE]
234: Adv Space Res. 1989;9(10):333-6.
Behavioral and neurochemical abnormalities after exposure to low doses
of
high-energy iron particles.
Hunt WA, Joseph JA, Rabin BM.
Behavioral Sciences Department, Armed Forces Radiobiology Research
Institute,
Bethesda, MD 20812-5145, USA.
Exposure of rats to high-energy iron particles (600 MeV/amu) has been
found to
alter behavior after doses as low as 10 rads. The performance of a task
that
measures upper body strength was significantly degraded after
irradiation. In
addition, an impairment in the regulation of dopamine release in the
caudate
nucleus (a motor center in the brain), lasting at least 6 months, was
also found
and correlated with the performance deficits. A general indication of
behavioral
toxicity and an index of nausea and emesis, the conditioned taste
aversion, was
also evident. The sensitivity to iron particles was 10-600 times
greater than to
gamma photons. These results suggest that behavioral and
neurobiological damage
may be a consequence of exposure to low doses of heavy particles and
that this
possibility should be extensively studied.
PMID: 11537313 [PubMed - indexed for MEDLINE]
235: Brain Res. 2001 Jun 15;904(1):43-53.
Effects of low intensity radiofrequency electromagnetic fields on
electrical
activity in rat hippocampal slices.
Tattersall JE, Scott IR, Wood SJ, Nettell JJ, Bevir MK, Wang Z,
Somasiri NP,
Chen X.
Slices of rat hippocampus were exposed to 700 MHz continuous wave
radiofrequency
(RF) fields (25.2-71.0 V m(-1), 5-15 min exposure) in a stripline
waveguide. At
low field intensities, the predominant effect on the electrically
evoked field
potential in CA1 was a potentiation of the amplitude of the population
spike by
up to 20%, but higher intensity fields could produce either increases or
decreases of up to 120 and 80%, respectively, in the amplitude of the
population
spike. To eliminate the possibility of RF-induced artefacts due to the
metal
stimulating electrode, the effect of RF exposure on spontaneous
epileptiform
activity induced in CA3 by 4-aminopyridine (50-100 microM) was
investigated.
Exposure to RF fields (50.0 V m(-1)) reduced or abolished epileptiform
bursting
in 36% of slices tested. The maximum field intensity used in these
experiments,
71.0 V m(-1), was calculated to produce a specific absorption rate
(SAR) of
between 0.0016 and 0.0044 W kg(-1) in the slices. Measurements with a
Luxtron
fibreoptic probe confirmed that there was no detectable temperature
change (+/-
0.1 degrees C) during a 15 min exposure to this field intensity.
Furthermore,
imposed temperature changes of up to 1 degrees C failed to mimic the
effects of
RF exposure. These results suggest that low-intensity RF fields can
modulate the
excitability of hippocampal tissue in vitro in the absence of gross
thermal
effects. The changes in excitability may be consistent with reported
behavioural
effects of RF fields.
PMID: 11516410 [PubMed - indexed for MEDLINE]
236: Biull Eksp Biol Med. 1994 Dec;118(12):606-8.
[Correction of disruptions in learning and memory, caused by the effect
of
superhigh frequency electromagnetic emissions, by nootropic drugs]
[Combined effect of noise and electromagnetic fields of industrial
frequency
(experimental study)]
[Article in Russian]
Khudnitskii SS, Murzenok PP, Vikent'eva NK, Tsykhun GF, Netukova NI.
PMID: 10420718 [PubMed - indexed for MEDLINE]
238: Gig Tr Prof Zabol. 1980 Feb;(2):46-7.
[Calcium and magnesium content in the tissues of rats exposed to an
industrial-frequency electromagnetic field]
[Article in Russian]
Dyshlovoi VD, Radlovskaia ZT, Arkhipchuk VD, Kachura VS.
PMID: 7378163 [PubMed - indexed for MEDLINE]
239: Aviakosm Ekolog Med. 1997;31(2):38-43.
[Combined effects of various forms of motor deprivation and gamma
irradiation on
the higher nervous activity in rats]
[Article in Russian]
Shtemberg AS.
Effects of gamma-radiation at a dose of 3 Gy against either
antiorthostatic
hypodynamia (AOH) or hypokinesia (HK) on formation of the differentiated
motor-drinking reflex (DR) were compared. Each of the forms of motor
deprivation
hindered the elaboration of DR; gamma-irradiation aggravated these
disorders. At
the same time, AOH led to significantly more severe disturbances in the
higher
nervous activity including the generalized excitation, pathologic
aggressiveness
and neurotization of animals. In contrast, hypokinesia stimulated the
active
elements of behavior which inhibit the passive-defensive behavior and a
fear
reaction. Therefore, the modifying effect of irradiation becomes
apparent only
if combined with AOH.
[Forming of memory (imprinting) in chicks after prior low-level
exposure to
electromagnetic fields]
[Article in Russian]
Grigor'ev IuG, Stepanov VS.
State Research Centre of Russia-Institute of Biophysics, Moscow.
EMF of power density from 0.4 to 10 mW/cm2 can influence forming the
memory
(imprinting). Showed the possibility to fix EMF modulated in embryonic
brain
during the natal period and conservation of this information after
birth.
PMID: 9633625 [PubMed - indexed for MEDLINE]
241: Dtsch Zahnarztl Z. 1982 Feb;37(2):187-90.
[Animal experiment studies of the question of radiogenic caries]
[Article in German]
Vogel C, Reichart P, Hassenstein E, Ronneberger H.
PMID: 6951707 [PubMed - indexed for MEDLINE]
242: J Cutan Pathol. 2003 Feb;30(2):135-8.
Effects of electromagnetic radiation from a cellular telephone on
epidermal
Merkel cells.
Irmak MK, Oztas E, Yagmurca M, Fadillioglu E, Bakir B.
Department of Histology and Embryology,Gulhane Military Medical
Academy, Ankara,
Turkey. mkirmak@gata.edu.tr
The number of reports on the effects induced by electromagnetic
radiation (EMR)
from cellular telephones in various cellular systems is still
increasing. Until
now, no satisfactory mechanism has been proposed to explain the
biological
effects of this radiation except a role suggested for mast cells.
Merkel cells
may also play a role in the mechanisms of biological effects of EMR.
This study
was undertaken to investigate the influence of EMR from a cellular
telephone
(900 MHz) on Merkel cells in rats. A group of rats was exposed to a
cellular
telephone in speech position for 30 min. Another group of rats was
sham-exposed
under the same environmental conditions for 30 min. Exposure led to
significantly higher exocytotic activity in Merkel cells compared with
the sham
exposure group. This finding may indicate the possible role of Merkel
cells in
the pathophysiology of the effects of EMR.
PMID: 12641793 [PubMed - in process]
243: Bioelectromagnetics. 1998;19(2):136-8.
Comment on:
Bioelectromagnetics. 1997;18(2):111-5.
Extremely low frequency electromagnetic fields do not interact directly
with
DNA.
Adair RK.
Department of Physics, Yale University, New Haven, Connecticut 06516,
USA.
Blank and Goodman [(1997): Bioelectromagnetics 18:111-115] suggest that
weak
extremely low frequency (ELF) electric and magnetic fields affect
intracellular
DNA directly. We show that such a conclusion is not in accord with
physical
principles.
[Permeability of erythrocyte membranes from peripheral blood after
exposure to
low-frequency alternating electromagnetic field]
[Article in Russian]
Levshin IV.
The levels of dienic conjugates (DC), malonic dialdehyde (MD),
extra-erythrocytic hemoglobin, the rate of chemiluminescence (C), total
peroxidase activity (TPA) were determined on a single exposure of
animals to
low-frequency pulsating electromagnetic field (LFPEF) and chronic
exposure of 16
healthy males aged 19-25 years. After acute exposure to LEPEF, the
animals
showed 64-106% increases in the levels of DC and MD and the rate of C.
The
persons had higher TPA and C.
PMID: 8183583 [PubMed - indexed for MEDLINE]
245: IEEE Trans Biomed Eng. 1981 Mar;28(3):258-64.
Measurements of the RF power absorption in spheroidal human and animal
phantoms
exposed to the near field of a dipole source.
Iskander MG, Massoudi H, Durney CH, Allen SJ.
PMID: 7228071 [PubMed - indexed for MEDLINE]
246: Gig Sanit. 1989 Jun;(6):84-6.
[Evaluation of the work capacity of laboratory animals in a toxicologic
experiment]
[Article in Russian]
Fedotov VP, Moskalev OS, I'lin BN.
PMID: 2792810 [PubMed - indexed for MEDLINE]
247: Aviakosm Ekolog Med. 1998;32(5):40-5.
[Evaluation of individual radiation resistance of rats based on
reactions to
non-radiation testing]
[Article in Russian]
Shtemberg AS, Farber IuV, Shafirkin AV.
Presented are the data on radiation sensitivity of various groups of
animals
preliminary differentiated by their tolerance of acute hypoxia. The
processes of
blood forming system impairment and reparation are detailed. As was
shown,
highly resistant to hypoxia rats are distinguished by the best radiation
resistance. Survivability of these rats was significantly higher as
compared
with other groups of animals. Recovery of blood formation by both the
red and
white chits following exposure to [symbol: see text] of the mean lethal
dose
proceeded more rapidly in the radiation resistant rats.
[Effects of electromagnetic radiation of various modes on heart
activity (in
experiments)]
[Article in Russian]
Afrikanova LA, Grigor'ev IuG.
On spinal cord frogs and isolated interauricle to a partition of heart
in vivo
and in vitro influence the MICROWAVES of a radiation in continuous and
modulated
modes on function of heart (9.3 Hz is investigated; 0.348-0.16 and
0.016 mV/sm2,
modulation from 1 up to 100 Hz). A possibility of influence of an
electromagnetic exposure on heart frequency and rhythm is revealed.
Pointing of
heart in vitro by a neutral red resulted in large number of % of
experience in a
stop of irradiated heart.
PMID: 9019279 [PubMed - indexed for MEDLINE]
249: Child Dev. 1968 Dec;39(4):1247-52.
Newborn activity and emotional response at eight months.
McGrade BJ.
PMID: 5704397 [PubMed - indexed for MEDLINE]
250: Percept Mot Skills. 2000 Apr;90(2):659-74.
Experimental simulation of a haunt experience and elicitation of
paroxysmal
electroencephalographic activity by transcerebral complex magnetic
fields:
induction of a synthetic "ghost"?
Persinger MA, Tiller SG, Koren SA.
Department of Psychology, Laurentian University, Sudbury, Ontario,
Canada.
To test the hypothesis that experiences of apparitional phenomena with
accompanying fear can be simulated within the laboratory, a 45-yr.-old
journalist and professional musician who had experienced a classic
haunt four
years previously was exposed to 1 microTesla, complex, transcerebral
magnetic
fields. Within 10 min. after exposure to a frequency-modulated pattern
applied
over the right hemisphere, the man reported "rushes of fear" that
culminated in
the experience of an apparition. Concurrent electroencephalographic
measurements
showed conspicuous 1-sec.-to-2-sec. paroxysmal complex spikes (15 Hz)
that
accompanied the reports of fear. A second magnetic field pattern,
applied
bilaterally through the brain, was associated with pleasant
experiences. The
subject concluded that the synthetic experience of the apparition was
very
similar to the one experienced in the natural setting. The results of
this
experiment suggest that controlled simulation of these pervasive
phenomena
within the laboratory is possible and that this experimental protocol
may help
discern the physical stimuli that evoke their occurrence in nature.
PMID: 10833767 [PubMed - indexed for MEDLINE]
251: Vopr Onkol. 1996;42(5):13-21.
[Super-low frequency electric and magnetic fields and their role in
development
of neoplasms]
Analgetic effect of low-intensive frequency-modulated millimetric waves
(MW) was
studied in mice with formalin induced nociceptive behavior reaction
(licking of
defeat hindpaw). MW were applied to the acupoint E 36 of the defeat
hindpaw. The
following MW were used: 60 GHz (1) and 118 GHz (2) which were modulated
by 4 Hz;
noise MW within the range of 42-95 GHz (3) and 90-140 GHz (4) which were
modulated in accidental order by frequencies 1-60 Hz; combinations of
fixed
frequencies with noise - 60 GHz + noise 42-95 GHz (5) and 118 GHz +
noise 90-140
GHz (6). All used MW combinations suppressed licking of the defeat
hindpaw and
increased duration of sleep and eating. The strongest analgesia was
achieved in
series 1-3 (42.4-69.7%), the weakest in series 6 and 4 of the experiment
(12.2-19.7%).
PMID: 11008563 [PubMed - indexed for MEDLINE]
253: Zh Vyssh Nerv Deiat Im I P Pavlova. 1982 Nov-Dec;32(6):1096-103.
[Probabilistic characteristics of "open field" behavior in the rat]
An analysis was made of the dynamics of probabilistic characteristics
of the rat
behaviour in the process of extinction of orienting-investigating
behaviour in
the "open field". Estimation of the entropy value related to behaviour
permitted
to divide the rats into two groups. The rats with high entropy values
differed
from those with low values by a more prolonged retention of a high
level of
locomotion, vertical stands, wall stands, peeping through a hole and
grooming.
It is suggested that a high entropy level and prolonged retention in the
behaviour pattern of most of the elementary acts and poses may testify
to a
delayed process of extinction of orienting-investigating activity due
to a
higher level of the rats negative emotional state.
PMID: 7164573 [PubMed - indexed for MEDLINE]
254: Lik Sprava. 1997 May-Jun;(3):83-7.
[The interaction of changes in the genitalia in the pathogenesis of
sterility in
men]
[Article in Ukrainian]
Malyshkin IN.
Alterations in testicular structures on the side of the pathologic
process,
contralateral testicle, epididymis, deferent duct, prostate,
spermogramme, were
found out to be related to the level of gonadotrophic and sex hormones
in
pathogenesis of infertility developing in varicocele, cryptorchidism,
epididymitis, prostatitis, obstruction of the deferent duct, and action
of low
frequency electromagnetic field. The findings obtained will, we
believe, help in
diagnosing and prescribing the pathogenetically substantiated treatment.
PMID: 9377363 [PubMed - indexed for MEDLINE]
255: Dokl Akad Nauk. 1994 Jun;336(6):826-8.
[Effect of a low-energy pulse of EHF and SHF-radiation of nanosecond
duration
with a high peak intensity on biological structures (malignant
neoplasms)]
[Mechanism of radiobiological effects of low intensity nonionizing
electromagnetic radiation]
[Article in Russian]
Kudriashov IuB, Perov IuF, Golenitskaia IA.
Moscow State University, Department of Biology.
The results of the research of the biological effects of the
non-ionizing
electromagnetic radiation were studied from the position of "thermal"
and
"unthermal" mechanisms. The special attention was spared to analysing
the
information characterising the high sensitiveness of the human and
animals
organism to the very-low intensity electromagnetic fields.
[Possible modification of radiation injury using radio frequency
electromagnetic
radiation]
[Article in Russian]
Aminova EM, Ismailov ESh.
Daghestan State Polytechnic University, Makhach-Kala.
The possibility of radioprotective action of electromagnetic fields and
radiations in radiofrequency range have been considered. It has been
shown that
the EMF and EMR effects depend on parameters of acting field. It is
necessary to
establish biophysical and biochemical ways and mechanisms of EMF and
EMR action
for effective use of radioemissions as radioprotectors.
Publication Types:
Review
Review, Tutorial
PMID: 10366968 [PubMed - indexed for MEDLINE]
260: Med Tr Prom Ekol. 1997;(5):24-30.
[Features of the relationship of electromagnetic fields and biological
objects
and their shielding]
[Article in Russian]
Miroshnikova TK.
PMID: 9235214 [PubMed - indexed for MEDLINE]
261: Biofizika. 1997 May-Jun;42(3):738-41.
[Molecular mechanisms of biological action of low magnetic fields. II.
Purification and characteristics of protein from rat brain chromatin
which
inhibit DNAse 1 activity]
[On the mechanism of cytogenetic effect of electromagnetic radiation: a
role of
oxidation homeostasis]
[Article in Russian]
Brezitskaia HV, Timchenko OI.
Ukrainian Scientific Centre of Hygiene, Ministry of Health of Ukraine,
Kiev.
It was established in the experiments on rats that the changes in free
radical
oxidation under the influence of non-ionizing radiation had a wavy
character. It
was revealed that the changes in oxidation homeostasis preceded
development of
cytogenetic effects and could be their reason.
PMID: 10819036 [PubMed - indexed for MEDLINE]
263: Acta Anat (Basel). 1992;145(4):302-6.
Influence of continuous electromagnetic fields on the stage, weight and
stature
of the chick embryo.
Piera V, Rodriguez A, Cobos A, Torrente M, Cobos P.
Department of Basic Medical Sciences, University of Barcelona, Faculty
of
Medicine, Reus, Tarragona, Spain.
The influence of continuous electromagnetic fields (0, 181 or 361
Gs/cm2) on the
development of chick embryo (n = 144) was studied. Several parameters
were
determined at days 5, 10 and 15 of incubation: stage (following
Hamburger and
Hamilton), vertex-coccyx length (size) and weight. At 5 days of
incubation, all
embryos showed a similar stage. However, at days 10 and 15, the embryos
exposed
to 181 Gs/cm2 showed a stage significantly superior to that of the
others. There
were no differences between the exposed embryos and the control ones
with regard
to weight and stature, except at 15 days when the embryos exposed to
361 Gs/cm2
showed greater weight and stature than those of the controls.
PMID: 10457769 [PubMed - indexed for MEDLINE]
264: Gig Sanit. 1999 May-Jun;(3):48-51.
[The current problems of electromagnetic safety in computer classes]
He paper presents the data on the present-day situation in the computer
classes
in general educational schools to show electromagnetic safety. It shows
that
most of 37 classes do not satisfy the requirement of electromagnetic
safety and
proposes modes of elimination of this danger.
[The general patterns in the development of the ultrastructural
reactions under
the action of electromagnetic radiations]
[Article in Russian]
Korolev IuN.
Original investigations of the author provided authors with information
on
subcellular adaptive reactions in response to electromagnetic radiation.
Activation of hyperplastic processes represents the leading
structural-adaptive
response of the body arising accelerated renewal of the
ultrastructures. The
author characterizes adaptive hyperplasia of the ultrastructures. The
author
characterizes adaptive hyperplasia emerging in bioenergetic and
protein-synthetizing organelles in the cells of different organs. It is
emphasized that high intensities provoke destructive processes.
PMID: 9446304 [PubMed - indexed for MEDLINE]
266: Fiziol Zh Im I M Sechenova. 1995 Dec;81(12):115-20.
[The erythrocyte reaction of the moving blood in mammals to the action
of
permanent and pulsed low-frequency electromagnetic fields]
267: Indian J Biochem Biophys. 1999 Oct;36(5):337-40.
Effect of amplitude modulated RF radiation on calcium ion efflux and ODC
activity in chronically exposed rat brain.
Paulraj R, Behari J, Rao AR.
School of Environmental Sciences, Jawaharlal Nehru University, New
Delhi.
The effect of exposing rats to amplitude modulated radiofrequency
radiation (112
MHz modulated to 16 Hz) during development and growth has been
examined. Wistar
rats (35 days old) when exposed at above frequency at the power level
1.0 mW/cm2
(SAR, 0.75 W/kg) for 35 days showed enhanced ornithine decarboxylase
activity
and Ca2+ efflux in brain indicating potential health hazards due to
exposure.
PMID: 10844985 [PubMed - indexed for MEDLINE]
268: Prog Brain Res. 2000;122:105-15.
Neurobiological correlates of defensive behaviors.
Bakshi VP, Shelton SE, Kalin NH.
Department of Psychiatry, University of Wisconsin at Madison, Wisconsin
Psychiatric Institute and Clinics 53719, USA.
Publication Types:
Review
Review, Tutorial
PMID: 10737053 [PubMed - indexed for MEDLINE]
269: Zh Vyssh Nerv Deiat Im I P Pavlova. 1984 May-Jun;34(3):537-46.
[Individual features of rat behavior: manifestations of anxiety]
[Article in Russian]
Khonicheva NM, Dmitrieva IL, Krushinskaia NL, Voronina TA.
Motor agitation developing in some white rats during painful
stimulation of
other individual decreases under the action of phenasepam (the most
effective
drug used in clinic in cases of neurotic alarm). This effect is
accompanied by
strengthening of tendency to reside in closed space. After phenasepam
injection,
increased not goal-directed motor activity developing against the
background of
reduced alimentary reactions also decreases in a part of grey rats
selected by
their ability to extrapolate, while their alimentary behaviour
intensifies.
Thus, initial peculiarities of behaviour i.e. enhanced motor activity
not
directed to fulfillment of the above forms of inborn behaviour
(residing in
closed space and eating) may be considered as a manifestation of
anxiety. In
this case, these forms of behaviour have a defensive function.
PMID: 6540937 [PubMed - indexed for MEDLINE]
270: Fiziol Zh SSSR Im I M Sechenova. 1980 Feb;66(2):263-7.
[Effect of radiowaves of nonthermal frequencies on the content of
somatotropic
hormone in the rat adenohypophysis]
[Article in Russian]
Demokidova NK.
PMID: 7364125 [PubMed - indexed for MEDLINE]
271: Tsitologiia. 2000;42(1):92-5.
[Activity of the genome of cardiomyocytes as an indicator of the
development of
adaptive changes in the myocardium following exposure of the central
nervous
system to electromagnetic fields]
Russian Scientific Centre of Rehabilitating Medicine and Health Resort
Cure,
Moscow.
Methods of cardiomyocyte nuclei isolation from the myocard homogeneous
mixture,
and of cardiomyocyte genome activity estimation were elaborated. In the
experiments with hyperlipoproteidemic rats, cardiomyocyte genome
activity was
shown to reflect the primary adaptive changes in the myocard, and to
serve a
reliable index of their influence on the CNS regulatory centres exposed
to
electromagnetic field, which is used for hyperlipoproteidemia
treatment. The
cardiomyocyte genome activity was used to distinguish between three
types of
development of adaptive reactions in the myocard.
PMID: 10709259 [PubMed - indexed for MEDLINE]
272: Physiol Behav. 1974 Mar;12(3):393-8.
Immediate behavioral responses of an echinoderm to ionizing radiations.
Dedrick MC, Kimeldorf DJ.
PMID: 4856540 [PubMed - indexed for MEDLINE]
273: Health Phys. 1971 Apr;20(4):421-4.
Effects of 800-MHz electromagnetic radiation on body weight, activity,
hematopoiesis and life span in mice.
Spalding JF, Freyman RW, Holland LM.
PMID: 5569217 [PubMed - indexed for MEDLINE]
274: Med Tr Prom Ekol. 2000;(5):32-5.
[The evaluation of the consequences of electromagnetic irradiation of
hands in
operators of high-frequency welding devices]
[Article in Russian]
Rudakov ML.
Method of secondary sources (method of integral equations) was applied
to
calculate specific absorbed intensity in hands of operators working at
non-shielded high-frequency (27.12 Mhz) welding devices. The authors
present
calculations for "female" and "male" hand sizes, give recommendations
on lower
level of specific absorption.
PMID: 10881543 [PubMed - indexed for MEDLINE]
275: Pol Tyg Lek. 1985 Nov 18-25;40(46-47):1304-7.
[Anxiety level and duration of the disease in patients with leukemia]
[Article in Polish]
Wrona-Polanska H.
PMID: 4094938 [PubMed - indexed for MEDLINE]
276: Psychol Rep. 1973 Dec;33(3):731-6.
Swim-tank measurement of radiation-induced behavioral incapacitation.
Casarett AP.
PMID: 4767829 [PubMed - indexed for MEDLINE]
277: Biull Eksp Biol Med. 2000 Jan;129(1):100-2.
[[Effects of fractions of the cerebrospinal fluid from patients with
drug
addiction treated by liquor sorption on the behavior of rats-recipients]
[Hygienic regulation of electromagnetic radiation of 300-3000 MHz
frequency
range]
[Article in Russian]
Kol'chugin IuI.
The article contains analysis of national standards determining maximal
allowable levels of electromagnetic exposure in some developed
countries. The
point of specific interest is the levels in frequency range of 300
MHz-30 GHz,
as this range is widely used in most apparatus for mobile communication.
Different in various countries, values of the maximal allowable levels
appear to
be the most strict in Russia. Incomplete knowledge of long-standing
exposure to
mild electromagnetic fields requires through medical and technical
research to
determine limits of safe application of mobile communication devices.
PMID: 9019326 [PubMed - indexed for MEDLINE]
280: Bioelectromagnetics. 1984;5(1):31-8.
Offset of the vacuolar potential of Characean cells in response to
electromagnetic radiation over the range 250 Hz-250 kHz.
Montaigne K, Pickard WF.
Measurements were made of the small, transient offsets of vacuolar
potential
produced in single cells of Nitella flexilis and Chara braunii by
isolated
bursts of audio frequency electromagnetic radiation. The offsets
increased in
magnitude with decreasing frequency of the electromagnetic radiation
and, below
about 6 kHz, seemed to approach a low-frequency asymptote. This
frequency
dependence for the offset is shown to be in accordance with a previously
developed model in which the incident radiation is weakly rectified by
the
cell's membrane system.
PMID: 6712748 [PubMed - indexed for MEDLINE]
281: Kosm Biol Aviakosm Med. 1981;15(3):26-8.
[Emotional reactions and cardiac rhythm slow waves]
[Article in Russian]
Karpov AN, Zinov'eva LA.
Simulation studies of various emotional reactions of operators have
shown that
sthenic emotional reactions induce inhibition of slow waves of cardiac
rhythm
(f=0.05 divided by 0.17 Hz,) whereas asthenic emotional reactions lead
to
excitation of slow waves in the above frequency range.
PMID: 7289540 [PubMed - indexed for MEDLINE]
282: Dokl Akad Nauk. 1995 Oct;344(6):840-2.
[Coenzyme Q (ubiquinone) as a behavioural modifier in rats, subjected to
low-background ionizing radiation]
[Changes of neurocytes in CNS under general exposure to UHF field with
local
protection applied]
[Article in Russian]
Leshin VV.
Experiments on white rats were performed to study influence of UHF
field on
cortical sensomotor area under general exposure or with the head
shielded. The
changes in CNS caused by UHF field were not prevented completely by
means of the
shield. That is probably due to pathologic reflex impulses from the body
receptors.
PMID: 10881537 [PubMed - indexed for MEDLINE]
284: Med Hypotheses. 2000 May;54(5):685-8.
Biological effects of low-level environmental agents.
Kmecl P, Jerman I.
BION, Institute for Bioelectromagnetics and New Biology, Ljubljana,
Slovenia.
primoz.kmecl@guest.arnes.si
We compare three similar but different biological effects:
provocation-neutralisation treatment of non-antibody-mediated
hypersensitivities, hormesis and low-level effects in radiation
biology. All
three have not yet been fully explained but share some common and
interesting
properties: non-linear concentration dependence, typical stress pattern
and
typical immune response. We try to make a generalisation of the three
phenomena
in terms of the informational properties of the low concentrations, and
imply
the possible common mechanism. Copyright 2000 Harcourt Publishers Ltd.
PMID: 10859665 [PubMed - indexed for MEDLINE]
285: Izv Akad Nauk Ser Biol. 1997 Nov-Dec;(6):728-34.
[The destruction of microscopic organisms by their irradiation with a
special
form of UHF electromagnetic signals]
Electromagnetic signals of special form produced by an ultra-high
frequency
generator were used to destroy various microorganisms: baker's yeast;
blue-green
alga Nostoc muscorum; mold fungus; and two flagellates, plant
flagellate Euglena
gracilis and an animal flagellate parasitizing on humans. The control
samples
before irradiation and experimental samples damaged and destroyed by
irradiation
were examined on a microscope with a computer system of image analysis.
The
results are presented as computer graph images.
PMID: 9518060 [PubMed - indexed for MEDLINE]
286: Vopr Onkol. 1999;45(3):287-91.
[Assessment of antineoplastic action of dehydrogenases in peripheral
blood
lymphocytes in S-45 tumor-bearing rats exposed to weak
ultra-low-frequency
irradiation]
[Article in Russian]
Shiikhliarova AI, Sheiko EA, Pil' EA.
Research Institute of Oncology, Ministry of Health of the RF,
Rostov-on-Don.
The aim of the investigation was to study the antitumor action of weak
ultra
low-frequency magnetic field (ULFMF) and application of a spectrum of
dehydrogenases of peripheral blood lymphocytes as a sensitive indicator
of such
action in tumor S45-bearing rats. It was shown that application of weak
ULFMF
improves antitumor defenses and dehydrogenase activity tends to stay
normal. The
dehydrogenase activity of peripheral blood lymphocytes can be used to
assess
immune system tension and synchronization of resistance processes.
PMID: 10443233 [PubMed - indexed for MEDLINE]
287: Wiad Lek. 1999;52(3-4):174-7.
[Anxiety as a anesthesiological problem]
[Article in Polish]
Chmielnicki Z.
Oddzialu Anestezjologii i Intensywnej Opieki Pooperacyjnej,
Wojewodzkiego
Szpitala, Specjalistycznego w Tychach.
Fear is a feeling which always accompanies people. It is a compound
phenomenon,
which has different components as psychologic, motor,
somatic-vegetative and
metabolic. The operation and anesthesia increase the feeling of
anxiety. The
dimension of the fear has the inconvenient influence on the time of
recovery,
quantity of complications and the discomfort felt by patients. The
dimension of
the fear can be measured in many ways. The questionnaires are one of
the methods
of taking an objective measurement. The STAI is one of the most often
used
between them. It enables the estimation of the efficacy of the
preoperative
preparing methods and the dynamics of the fear during the
hospitalization.
Monitoring of the anxiety can be very useful in the decreasing the fear.
Publication Types:
Review
Review, Tutorial
PMID: 10499029 [PubMed - indexed for MEDLINE]
288: Med Tr Prom Ekol. 1999;(6):31-4.
[Occupational assessment of computer placement in school areas]
The study included measurements of electromagnetic radiation emitted by
MACINTOSH PC placed in public schools, functional state examination of
schoolchildren sitting in rows in front of PCs. Electromagnetic
radiation
emitted by PCs appeared to harm higher nervous activity of the
schoolchildren.
With consideration of the studies conducted the recommendation is not
to set
workplaces in rows. The workplaces could be set perimetrically, with at
least
1.0 m between the lateral borders of neighboring monitors. Angle-wise
set
workplaces should stay at least 2.0 m apart.
PMID: 10420715 [PubMed - indexed for MEDLINE]
289: Radiat Res. 1974 Feb;57(2):288-99.
Damage of rat thyroid by 131I and evidence against immunologic
transferability.
White SC, Casarett GW.
PMID: 10874943 [PubMed - indexed for MEDLINE]
290: Z Gesamte Hyg. 1981 Oct;27(10):753-5.
[The collagen structure in subacute radiation sickness in the albino
rat]
[Article in German]
Drozdz M, Antoniewicz M, Kucharz E.
PMID: 7314704 [PubMed - indexed for MEDLINE]
291: Rev Esp Cardiol. 2000 Jun;53(6):881-2.
[Pacemakers, defibrillators, and electromagnetic environment: potential
interactions with electronic mechanisms of surveillance should not be
cause of
anxiety for patients]
Comment on:
Bioelectromagnetics. 1996;17(4):312-21.
Comments on "Resonance effect of millimeter waves in the power range
from
10(-19) to 3 X 10(-3) W/cm2 on Escherichia coli cells at different
concentrations," Belyaev et al., Bioelectromagnetics, 17:312-321 (1996)
Osepchuk JM, Petersen RC.
Full Spectrum Consulting, Concord, Massachusetts 01742, USA.
Publication Types:
Comment
PMID: 9338635 [PubMed - indexed for MEDLINE]
295: Gig Sanit. 1997 Sep-Oct;(5):61-3.
[Calculation of the average density of radiofrequency radiation power in
biological objects]
[Article in Russian]
Rudakov ML.
PMID: 9378358 [PubMed - indexed for MEDLINE]
296: Anim Behav. 1967 Oct;15(4):563-7.
The relationship between sensory stimulation and gross motor behaviour
during
the postnatal development in the rat.
Gard C, Hard E, Larsson K, Petersson VA.
PMID: 6055112 [PubMed - indexed for MEDLINE]
297: J Microw Power Electromagn Energy. 2000;35(3):179-84.
Complex high-frequency technology for protection of grain against pests.
Institute of Experimental and Clinical Veterinary Medicine, Ukrainian
Academy of
Agricultural Sciences.
The results of experimental investigation of physical methods are
presented for
suppressing of biological activity of grain and grain product pests:
harmful
insects at each developmental stage except eggs (Insecta), mites
(Arachnida,
Acariformes) and microscopic fungi and bacteria. The technologies under
development for disinfestation and disinfection of grain are based on
irradiation of grain by modulated pulses of high-frequency (HF)
electromagnetic
fields and on simultaneous action of a complex of factors: vacuum and
HF-field
induced plasma. The threshold value of the electric field intensity for
total
insect mortality was found to be E = 4.0-5.0 kV/cm in the pulse mode at
the base
frequency of 47.5 MHz. When the combined technology is used, conditions
are
created in the irradiation chamber for HF-discharge and plasma
formation, which
are very strong factors influencing the biological organisms. These
raise the
energy (and cost) efficiency (approximately $2-3 per tonne of grain) of
the
combined technology for destruction of grain pests with complete
environmental
safety.
[Preliminary data on radiosensitivity as a function of dose in rats
selected on
the basis of behavioral activity]
[Article in Italian]
Di Paola M.
PMID: 5617459 [PubMed - indexed for MEDLINE]
301: Med Hypotheses. 2000 Aug;55(2):160-3.
Human body frequency modulation by 0.9% sodium chloride solutions: a new
paradigm and perspective for human health.
Sudan BJ.
This case study demonstrates that the normal human body frequency,
which can be
disturbed by electromagnetic influences of the environment, can be
modulated by
0.9% sodium chloride solutions (physiological saline) and that
occurrence of
allergic reactions have subsequently been suppressed as a result of this
modulation. The use of distilled water as control showed no effect on
occurrence
of allergic reactions. Further observations on the growth of various
plants in a
greenhouse exposed to various geomagnetic fields support the previous
observations on humans. The neutralization of electromagnetic
influences on
humans using 0.9% sodium chloride solution or by enclosure of plants
within a
copper wire Faraday cage resulting in a normal and uniform growth of
plants as
compared with disturbed and irregular growth in unenclosed controls, is
demonstrated. These original observations propose a new strategy to
suppress or
prevent allergic reactions and possibly other effects observed in
various human
pathologies in relation to a disturbance of human body frequencies. It
is
hypothesized that the double helix structure of desoxyribonucleic acid
(DNA)
could be modified by environmental electromagnetic fields and that
disresonance
between the two chains of DNA could lead to the expression of specific
pathology. Copyright 2000 Harcourt Publishers Ltd.
PMID: 10904434 [PubMed - indexed for MEDLINE]
302: Lik Sprava. 1999 Jun;(4):51-6.
[Low-intensity electromagnetic radiation in medicine: a factor in
resonance
therapy or a nonspecific adaptogen?]
[Electromagnetic and mechanical vibrations in the therapy of myofascial
pains]
[Article in Russian]
Miriutova NF, Levitskii EF, Abdulkina NG.
Low-frequency vibration effectively stimulates in a direct way or via
reflexes
neuromuscular apparatus in patients with muscular-tonic manifestations
of spinal
osteochondrosis. Long-term myofixation forms foci of denervation
disorders as
painful muscular consolidations with active center the irritation of
which gives
rise to phenomenon of reflected pain. In this case it is better to begin
treatment with optic red and infrared radiation on the reflexogenic
zones and
muscular consolidations for reduction of trophic abnormalities. This
creates
favourable conditions for subsequent vibrostimulation of affected
nerves and
muscles.
PMID: 11094873 [PubMed - indexed for MEDLINE]
305: Dokl Biophys. 2000 Jan-Jun;370-372:21-4.
Effect of high-power microwave radiation with nanosecond pulse duration
on some
biological objects.
[Electromagnetic information in the phenomenon of life]
[Article in Russian]
Kuzin AM.
Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino,
Moscow
Region, Russia.
The author's original experiments and ideas have been summarized, which
concern
the role of natural background radiation in maintenance of
electromagnetic
information essential for existence of the living organism as an
integral whole.
Publication Types:
Review
Review, Tutorial
PMID: 10732224 [PubMed - indexed for MEDLINE]
307: Behaviour. 1965;25(1):45-97.
An experimental study of conflict and fear: an analysis of behavior of
young
chicks toward a mealworm. I. The behavior of chicks which do not eat the
mealworm.
A criticism of the study by McDowell and Merchent on fearfulness in
control and
irradiated rats. A reply to the preceding criticism by Smith and Dimond.
McDowell AA, Stolmeier PV.
PMID: 5365005 [PubMed - indexed for MEDLINE]
311: Gig Tr Prof Zabol. 1971;15(2):17-21.
[Effect of an industrial frequency electric field on motor dominant
formation]
[Article in Russian]
Sazonova TE.
PMID: 5090847 [PubMed - indexed for MEDLINE]
312: Int J Biometeorol. 1973 Sep;17(3):277-84.
[Influence of negative atmospheric ions on adaptation to an anxiety
situation in
rats]
[Article in French]
Olivereau JM.
PMID: 4756241 [PubMed - indexed for MEDLINE]
313: Biofizika. 2000 Sep-Oct;45(5):950-3.
[Chronobiological analysis of subarctic features of long-term dynamics
of
biological processes]
[Article in Russian]
Kashulin PA, Roldugin VK.
Arctic-Alpine Botanical Garden-Institute, Kola Research Center, Russian
Academy
of Sciences, Kirovsk, Russia.
The analysis of a large number of chronobiological observations
(heliospheric
modulations, cosmophysical factors, weak low-frequency electromagnetic
influences, etc.) allows us to make a conclusion about the possibility
of direct
and indirect exogenous (relative to the biosphere) modulations of
biological
processes in avroral and arctic zones. A nonequivalence of various
seasons for
the performance of introduction experiments was established. It was
shown that
the intensive fluctuations of environmental conditions are very
important for
the survival of living forms introduced into subarctic regions.
PMID: 11094729 [PubMed - indexed for MEDLINE]
314: NITA. 1982 Nov-Dec;5(6):374.
Patient emotional response to intravenous therapy.
Brown EA.
PMID: 6924083 [PubMed - indexed for MEDLINE]
315: Nerv Sist. 1969;10:177-83.
[Registration of electromagnetic fields arising during the movements of
insects,
birds and animals]
[Article in Russian]
Guliaev PI, Zabotin VI, Shlippenbakh NIa.
PMID: 5404169 [PubMed - indexed for MEDLINE]
316: Psychol Rep. 1965 Oct;17(2):595-602.
Behavioral effects of stimulation by UHF radio fields.
Eakin SK, Thompson WD.
PMID: 5833745 [PubMed - indexed for MEDLINE]
317: Am Ind Hyg Assoc J. 1996 Jun;57(6):576.
A missing factor?
Ely TS.
Publication Types:
Letter
PMID: 8651079 [PubMed - indexed for MEDLINE]
318: Anim Behav. 1967 Oct;15(4):574-85.
Changes in the behaviour of Lebistes reticulatus upon a repeated shadow
stimulus.
Russell EM.
PMID: 6055114 [PubMed - indexed for MEDLINE]
319: PHYSICAL REVIEW LETTERS. 1992 Feb 17;68(7):946-949.
Frequency upconversion of electromagnetic radiation upon transmission
into an
ionization front.
Savage RL Jr, Joshi C, Mori WB.
PMID: 10046039 [PubMed - as supplied by publisher]
