PubMed Health⌕ Search

Biomedical subjects

B V Zhuravlev

Publications and source records attributed to B V Zhuravlev.

At least 19 recordsLinked to original sources
PubMed2003

Dynamics of neuronal, autonomic, and motor measures in animals performing an acquired habit.

Previously obtained results and data from other groups showing that intersignal activity in animals correlates with the success of acquisition of defensive and food-procuring behavior are presented. In addition, specific changes in neuron activity and in the dynamics of cardiac and respiratory activity are demonstrated during performance of intersignal behavioral acts. The moments of appearance of intersignal activity were studied, as were patterns of changes in neurophysiological measures during different types of intersignal actions. The first series of experiments showed that different contextual stimuli (mainly ratios of sector illumination, which are ethologically important for rats) have significant effects on the level of intersignal activity and the success of learning active defensive behavior. The next series of experiments, in which learning and extinction of a passive defensive habit in rabbits were performed, demonstrated the existence of two types of intersignal activity. The first type was characterized by repetition of pain reinforcement parameters in the structure of changes in neurophysiological measures during intersignal behavior; the second type was characterized by a coincidence of the whole structure of neuronal activity, cardiac rhythm, and respiration during intersignal activity with the dynamics of these measures during the conditioned reflex behavioral act. This study suggests that the process of intersignal extraction of an efferent program for acquired defensive behavior may be one of the mechanisms by which it is fixed in memory and plays an important role in the animal's achievement of useful adaptive results.

Acoustic Stimulation↗
PubMed2002

[The dynamics of neuronal, autonomic and movement parameters in animals during the reproduction of a learned habit].

Data by the authors, as well as from other laboratories, show that the intertrial responses correlated with accuracy of avoidance or feeding behaviour. Moreover our previously data demonstrated the definite changes of neuronal activity, heart rate and respiration during intertrial responses. In this study we investigated the time-course of intertrial response appearance, the pattern of neurophysiological parameters during intertrial periods, and the types of intertrial responses. Experiment 1 showed that different environmental stimuli influenced the level of intertrial responses and successfulness of the avoidance learning. In experiment 2, in which learning and extinction procedures were presented in rabbit passive-avoidance conditioning, two types of intertrial responses were observed; the first type repeated the pain reinforcement, the second one imitated the conditioned reaction of neuronal activity, heart rate, respiration, and moving. These investigations suggest that the processes of intertrial eliciting of avoidance effector programs may be one of the mechanisms of fixation in memory and play an important role in acquisition of more effective results.

Acoustic Stimulation↗
PubMed1990

Effects of medial septal stimulation & its blockade with atropine on hippocampal rhythmical slow activity in free-moving rabbits.

The influence of the medial septal nucleus (MSN) on hippocampal rhythmical slow activity (RSA) was investigated in hunger motivated free-moving rabbits. Single unit activity of 29 CA3 dorsal hippocampal neurones was studied under two paradigms viz., electrical stimulation (3v/1msec/5Hz) and chemical blockade of atropine-sensitive medial septal cells (dose of 5 micrograms in 5 microliters). The analysis of interspike interval sample histograms recorded with Apple II, along with single unit neuronal spikes recorded on polygraph showed bimodal pattern with two peaks; one at bin 10-20 (high frequency) and second at bin 100-300 (theta frequency). On stimulation of MSN, there was total suppression of bin 100-300 with peaks at bin 1-20 and at bin greater than 1000 (very low frequency). Blockade of cholinergic receptors at MSN showed reduction of bin 100-300 and peak at bin 700- greater than 1000; this was followed by gradual decrease of spike's amplitude and thereafter its total abolition. The results indicate that the septal region is not a pacemaker per se in the genesis of hippocampal RSA (theta rhythm), but serves more in the nature of a relay station for a number of inputs and that its influence on the hippocampal electrical activity depends on the integrity of cholinergic inputs, be it from hippocampus proper or from mid-brain reticular formation.

Animals↗
PubMed1989

[Effects of neuropeptide Y on behavior and noradrenaline level in the brain].

The administration of neuropeptide Y in lower doses (1 and 100 ng/rat) into the lateral ventricle of the brain gave rise to the inhibition of locomotor activity, weakening of the orienting-exploratory behaviour, increase in the period of rest in animals. Feeding and drinking behaviour after the administration of neuropeptide was not observed. Alterations of behaviour in rats were followed by a dose-depended increase in noradrenaline in hypothalamus. No changes were observed in the content of noradrenaline in the frontal cortex and septum. Some variations in the level of noradrenaline were found in amygdala and hippocamp. It may be assumed that behavioural effects, aroused by the central administration of neuropeptide Y, is connected with the activation of catecholaminergic systems of hypothalamus.

Animals↗
PubMed1986

[Amino acid composition and biological action of a peptide bioregulator from bovine k-casein].

Peptide material has been first isolated from k-casein pepsin hydrolysate. Its subcutaneous injection to hungry animals induced high amplitude (250-350 mV) and high frequency (16-20 Hz) oscillations of electrical potentials usually observed in food satiety and cholecystokinin administration. The peptide reduced respiratory and to a lesser extent heart rate. Its effect is temporary eliminated by naloxone. According to an aminogram, the peptide is a fragment of para-k-casein. A neurotropic peptide effect is connected with satiety regulation and milk consumption in the postnatal period.

Amino Acids↗
PubMed1980

[Analysis of food motivational stimulation on the level of thalamic neurons in the rabbit brain].

The activity of 34 neurons of the ventral and posteromedial nucleus of the thalamus, a transmissive link of the gustatory analyzer, was studied in fed rabbits before and after the alimentary reaction was produced by stimulation of the lateral hypothalamus. Of special interest is the appearance of bundle-like activity in 26.4% neurons in response to the stimulation of the lateral hypothalamus. This seems likely to reflect the involvement of neurons from the given nucleus of the hypothalamus into alimentary motivation excitation.

Animal Feed↗
PubMed1979

[Effect of parenterally administered amino acids and protein hydrolysate on the electrical activity of brain structures].

Glycin, glutamic acid or casein hydrolysate induced high frequency and high voltage electrical waves in the brain-stem RF and often in the lateral hypothalamic nucleus and cortex. These changes were more obvious during feeding of the dogs. Sham feeding and parenteral administration of glucose or 0.9% solution of NaCl evoked responses different from the above ones. Gastric secretion stimulated by i.v. administration of nitrous substances by food was not directly related to the above responses either. The impulses responsible for the secretion seem to arise at another level of the brain.

Amino Acids↗
PubMedDate not supplied

Systems analysis of the neuroimmunological mechanisms of memory.

Experimental data on the role of immunomodulators in the mechanisms of neurological memory are presented and assessed from the point of view of functional systems theory. It is demonstrated that the immunomodulator interleukin-1 beta and the alpha-2-interferon fragment RITLY improve the processes of learning and reproduction of an active defensive habit. These substances were found to have effects on the productivity of behavior, on orientational-investigative reactions, and on vocalization in response to a conditioned signal. A positive correlation between intersignal activity and productivity is demonstrated as a reflection of the mechanisms of anticipatory reorganization of behavior during learning. However, interleukin has a selective action depending on the ethological conditions obtained during learning.

Adjuvants, Immunologic↗
PubMedDate not supplied

[Characteristics of motor and cardiac activity in men during the performance of test "shooter"].

Subject's behavior and electrocardiogram were investigated during execution of the test "Shooter". Three kinds of strategies were used by subjects during the task performance. Three types of the motor activity of subjects were also found in the "interresulting" periods during the system activity. The spatial and temporal characteristics of these types of activity were similar to those during the actual achieving the result. Differences in the dynamics of the R-R-interval changes were found in the periods before achieving the positive or negative result.

Adult↗
PubMedDate not supplied

[Heterogeneity and physiological activity of bovine k-casein proteolysis products].

Gel chromatography in columns with Sephadex G-50 and biogel P-2 was used to separate a number of fractions formed in k-casein of cow's milk after short-term treatment with swine trypsin. These fractions, similar to beta-casomorphin, are capable of reducing the respiration and heart rates in rabbits after intravenous injection in a dose of 100 micrograms/kg, that suggests their capacity for interaction with opiate receptors. Some fractions injected subcutaneously induce in starving animals an electroencephalographic picture of satiation, similar to that observed after cholecystokinin injections. Correlation of amino acid composition and physiologic activity has evidenced that cholecystokinin and opioid effects are caused by different peptides.

Amino Acids↗
PubMedDate not supplied

[Effect of centrally administered cholecystokinin on feeding behavior induced by electric stimulation of the lateral hypothalamus in the rabbit].

In experiments on 15 freely moving rabbits cholecystokinin octapeptide sulfate (CCK-8-S) in a dose of 10 ng considerably suppressed alimentary behaviour of the animals elicited by electrical stimulation of the lateral hypothalamus. Increasing of the peptide doses to 100 and 200 ng elicited an analogous effect. CCK-8-NS in 10 ng dose produced a lesser effect on feeding of the animal, but increasing of the dose of nonsulphated CCK to 100 ng led to a considerable prolongation of feeding. CCK-8-S and CCK-8-NS in doses used did not affect the reaction of avoidance in rabbits caused by electrical stimulation of the ventromedial nucleus of the hypothalamus.

Animals↗