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Biomedical subjects

M G Aĭrapetiants

Publications and source records attributed to M G Aĭrapetiants.

At least 19 recordsLinked to original sources
PubMed1999

[Chronic stress increases the reactivity of central depressor mechanisms].

The activity of noradrenergic system of lateral hypothalamus and hemodynamics were studied during acute restraint in chronically stressed and control rats. Arterial blood pressure in rest was negatively proportional to basal norepinephrine concentration in dialysate of lateral hypothalamus. Animals with high increase of norepinephrine levels in dialysate during acute stress had rapid return of arterial blood pressure to basal values while stress-induced hypertension in the beginning of restraint was the same as in rats with low increase of norepinephrine levels. Data obtained show the depressor role of noradrenergic system of lateral hypothalamus. The enhanced reactivity of noradrenergic depressor system may be one of the mechanisms providing cardiovascular adaptation to stress.

Adaptation, Physiological↗
PubMed1990

[Effect of conditioned-reflex bilateral avoidance learning on lipid components of the rat brain].

The active avoidance training of rats resulted in a depletion of lipid peroxidation (LPO) products in cerebral cortex. LPO inhibition was also shown in cerebral cortex of "active control" group receiving +non-combined stimuli (the effect of short-term stress). LPO inhibition was more pronounced in rats staining a training criterion compared to rats which received combined stimuli but did not reach the criterion. In the active control group LPO inhibition was accompanied by total phospholipids accumulation and cholesterol depletion in cortical lipid extracts. Irrespective of attaining the criterion in all rats trained for active avoidance the accumulation of cholesterol was seen. Active avoidance training affected also the phospholipid composition of cerebral cortex.

Animals↗
PubMed1988

[Pharmacological correction of experimental alcoholic embryopathy].

In the experiments on the progeny of ethanol-exposed rats it was shown that consumption of 15% alcohol instead of water during pregnancy resulted in the worsening of shuttlebox avoidance learning and decrease in succinate dehydrogenase activity in the visual and sensorimotor cortex. These data are indicative of cerebral hypoxia during embryogenesis. The injection of synthetic opioid peptide dalargin during critical periods of development (at the end of embryogenesis and early ontogeny) prevented partially the disturbances of higher nervous activity and tissue breathing which were induced by alcohol intoxication. Possible mechanisms of positive dalargin effect are discussed.

Animals↗
PubMed1986

[Clinical and experimental studies of the role of neuromediator systems in the pathogenesis of neurosis and neurosis-like states].

Clinical studies revealed a significant increase in the peripheral blood levels of noradrenaline in patients with different forms of neurosis and neurosis-like states as compared to control subjects as well as heterogeneous or unidirectional but differently pronounced changes in blood levels of acetylcholine and adrenaline. Comparison of the clinical findings with the results of dynamic assays for peripheral levels of acetylcholine and catecholamine in dogs exposed to special psychogenic and physiogenic impacts has helped to form an understanding about some common mechanisms of the formation of neuroses and neurosis-like states. The authors emphasize the consistency of neuromediator shifts in the blood of patients and the possibility of using this parameter for the differential diagnosis of various forms of neurotic disturbances at the initial stage of the disease.

Acetylcholine↗
PubMedDate not supplied

[The activity of the monoaminergic systems of the rat hypothalamus in acute stress after chronic stressing].

The influence of chronic stress (footshock combined with randomized light flashes) on acute stress-induced (immobilization) release of noradrenaline, dopamine and serotonin in rat lateral hypothalamus was assessed by microdialysis. The chronic stress resulted in an increase and prolongation of the acute stress-induced release of noradrenaline but not of dopamine and serotonin. The increased rate of accumulation of dioxyphenylacetic acid and unchanged accumulation of homovanillic acid (dopamine metabolites) and dopamine during and after the acute stress in chronically stressed animals reflect a rise of synthetic activity of catecholaminergic systems in response to acute stress and reuptake increase. Marked stress-induced increase in hydroxyindoleacetic acid in chronically stressed rats without any changes in the ST dynamics may be regarded in a similar way. A significant increase in potassium-stimulated release of all the studied monoamines was found while their basal level remained unchanged. The conclusions was made that the hyperergic release of neurotransmitters may be the basis of an inadequate response of animals to acute stress, i.e., one of the neurotic symptoms.

Acute Disease↗
PubMedDate not supplied

[Effect of the short-term exposure to negative air ions on individuals with vegetative disorders].

The humans with vegetative disorder have been under the short-time exposition to negatively charged air ions, produced by Tchizhevski aeroionizer "Elion-132". The state of vegetative nervous system and some other physiological systems and organs of treated humans were estimated by acupuncture R. Voll method. It was found, that treatment by negatively charged air ions leads to the normalization of the state of mentioned above acupuncture points in the most (87%) of the tested humans with vegetative disorder. In 13% of tested persons these indicators became worse after this procedure. In the each case the changes in the state of different acupuncture points had the single-directed character. The suggestion was made, that vegetative nervous system plays the important role in the formation of organism's integrated reaction to the action of negatively charged air ions.

Adolescent↗
PubMedDate not supplied

[A trial of the use of aekol in preventing psychoautonomic disorders].

Autonomic dysfunction in chronic emotional stress is well documented. The aim of this study was to analyze the effects of natural antioxidant vitamin E (aekol). Twenty persons (16 women and 4 men, mean age 38 +/- 4 years) who reported recent occurrence of emotional stress were examined before and after a 4-week treatment with aekol (5 ml twice a day). Heart rate variability (taking into account very low-frequency (VLF, 0.003-0.04 Hz), low-frequency (LF, 0.04-0.15 Hz), and high-frequency (HF, 0.15-0.40 Hz) components) was computed from the power spectra (5-min epochs) of the EKG recorded in the patients in supine position. After the treatment, the HF power of the heart rate variability (an index of cardiac parasympathetic activity) increased (p < 0.05), whereas the VLF power (an index of the cerebral sympathetic activity) decreased (p < 0.01). The decrease in the VLF was accompanied by a reduction of anxiety level (p < 0.01). According to our hypothesis, the absolute and relative power of the VLF can be used as an index of anxiety or cerebral sympathetic activity, which significantly decreases after the aekol treatment.

Adult↗
PubMedDate not supplied

[The correction of the manifestations of a neurosis-like state in white rats by using the vitamin complex Aekol].

Behavior of neurotized white rats was studied in two experimental situations: during training for passive and active avoidance of electroshock applied to the limbs and during testing the acquisition of the conditioned avoidance. It was shown that in behavior of rats in the neurosis-like state the signs of anxiety and fear dominated, the orienting-exploratory behavior was suppressed. The state correction was performed by per os introduction of the natural vitamin complex Aekol during the neurotization of animals.

Animals↗
PubMedDate not supplied

[Correction by succinic acid of behavioral and physiological parameters of neurosis-like condition in white rats].

The neurosis-like state of white rats is accompanied by development of cerebral hypoxia. Negative symptoms of the neurosis-like state (behavioral, anatomic and energy) were decreased by per os administration of succinate (30 mg/kg) during the second half of the neurotization process. Succinate provided chiefly the delayed action on the system arterial tension, on the succinate dehydrogenase and NADH dehydrogenase activity. The effects depended on the propensity of a rat to the catatonic "freezing". The "freezing" was detected by a specific breathing pattern: a short inhale and a long pause. In "freezing" rats succinate corrected the system tension to a greater extent, while in "non-freezing" animals it corrected to a greater extent the succinate and NADH dehydrogenase activities. The positive effect of succinate administration is probably associated with its antihypoxic properties.

Animals↗
PubMedDate not supplied

[Study results and prospects in the pathogenesis of neuroses].

An attempt is made to highlight the modern state of investigations concerning the experimental neuroses, to show new branches in studying pathogenesis of neuroses. A new concept is substantiated on a participation of the cerebral circulatory hypoxia at neuroses. Is demonstrated a high efficiency of prophylaxis and therapy of neuroses using the anti-oxidants of anti-hypoxic action.

Animals↗
PubMedDate not supplied

[Study of trait anxiety in children with different profiles of lateral organization after early social deprivation].

School behavior and learning were examined in 68 right-, lefthanded, and ambidextral 10-12-year-old children earlier exposed to social deprivation. Socially deprived children revealed stress and high trait anxiety. "Imposed lefthandedness" is considered to be an important factor responsible for the high level of trait anxiety. In the group of socially deprived children persons with sanguinic temperament showed the lowest, and melancholies showed the highest levels of trait anxiety as compared to the control group.

Adolescent↗
PubMedDate not supplied

[A special case of learning disruption as a model of a disintegration phenomenon].

Combination of two factors in rats such as the isolation (during 2-4 months, beginning from the 21st day of age) and procedure of space cyclic learning results in a rare kind of behavioral strategy (in 30% animals), when the cyclic behavior is realized without food reinforcement. Such a dissociation between the vital motivation and searching behavior may be considered as an analogue of the disintegration phenomenon in neuropsychotic patients. The deep depression of learning owing to lowering of search represents the dominant type of behavioral disorders in isolants. The cyclic habit training, including a 2-months pause between two sessions, significantly increases behavioral search activity. The behaviors are accompanied by morphological shifts in the sensomotor cortex: significant decrease of the fifth layer (giant pyramids) thickness, selective lowering in the satellite glia density and elimination of normal behavior-glia correlations.

Animals↗
PubMedDate not supplied

[The influence of chronic neurotization on the monoaminergic systems of various brain structures in rats with various typological characteristics].

Typological behavioral features of Wistar rats were tested in the open field and in Porsolt test. Rats were assigned to groups with high (HAct), medium (MAct), and low (LAct) behavioral activities. The same rats were assigned to high (HDep), medium (MDep) and low depressive (LDep) groups. The release of norepinephrine, dopamine, serotonin and their metabolites in homogenates obtained from the hypothalamus, hippocampus, frontal cortex and amygdala was assessed by microdialysis and HPLC. In these groups, the monoamine concentrations were different: the level of serotonin was higher in the hypothalamus and norepinephrine and 5-HIAA levels were lower in the hippocampus of MAct - MDep rats as compared to LAct - HDep. Chronic neurotization caused changes in monoamine concentrations in the hypothalamus and amygdala in rats of all groups, whereas in the hippocampus and frontal cortex monoamine changes were observed in HAct - LDep and LAct -HDep rats. The most prominent changes in monoamines levels in neurotized rats with different types of behavior were found in the frontal cortex, amygdala and hippocampus. The results show a correlation between the typological of behavioral characteristics and the reaction to stress of monoaminergic systems of the hypothalamus, hippocampus, frontal cortex and amygdala.

Amygdala↗
PubMedDate not supplied

[Neuroses and their pathogenesis].

History and current state of the problem of experimental neuroses are reviewed in this article. The presented results of neurochemical, structural, and electroencephalographic investigations unravel earlier unknown aspects of the disease. Thus, circulatory cerebral hypoxia, as a principally new stage discovered for the first time in the development of an experimental neurosis allows the pathogenetically substantiated treatment with antioxidants to be applied in animal experiments and in clinical therapy of neurotic patients.

Animals↗