Effect of vasopressin on changes in the behavioral reactions of rats induced by psychotropic substances

The effect was studied of arginyl-8-vasopressin (AVP) on changes in rats behavioural reactions, elicited by reserpine, haloperidol, aminazine, amitriptyline or nialamide. It has been shown that AVP administered intraperitoneally in a dose of 0.001 mg/kg, eliminates the deficit of elaboration of conditioned reaction of active avoidance produced by psychotropic drugs, without influencing the motor activity reduction developed after administration of these substances.     

Effect of septal damage on alcoholic motivation in the rat

Interconnection between predisposition to depressive-like state (DS) in stress situation and heightened addiction to ethanol was studied in nonlinear male white rats. Electrolytic lesion of the septum in animals inclined to the development of DS, led to a change from the passive type of reaction in stress conditions to the active type. The rate of formation of alcoholic motivation in these animals decreased in comparison with sham-operated rats. The effect of the septal lesion in rats with formed addiction to alcohol was less expressed. Conclusion is made that the passive type of reaction in extreme conditions is significant for the formation of alcohol motivation in rats, especially at early stages.     

Evaluation of accelerated development of stable alcoholic motivation in rats for studying potential alcohol deterrents

The express technique reflecting an acquisition of a clear alcohol addiction during short-term voluntary alcoholization for further antialcoholic drugs testing was performed in male albino rats. By VARIMAX factor analysis of indexes related with preference of alcohol solutions with different tastes the conditions of short-term (2 months) voluntary alcoholization leading to persistent ethanol intake were studied. Isolation stress inducing a specific alcohol drive was excluded from rearing conditions. 0.1% saccharin solution in 15% ethanol was used for alcoholization. Statistical analysis revealed factor of "developed alcohol abuse" which may be detected in conditions of one-trail sweet ethanol intake after 3 days alcohol deprivation (similar to heavy drinking syndrome in humans). Using pharmacological drugs (pyrazidol, piracetam) validity of the method for specific drug design was confirmed.     

Effect of ethanol on the concentration of enkephalins in the brain of rats with different levels of alcoholic motivation

Radioimmunoassay was used to measure the content of leu- and met-enkephalins in white random-bred rats divided into groups according to the duration of ethanol anesthesia and the levels of 15% ethanol consumption under the conditions of free choice. The concentration of neuropeptides was determined in the cortex of the large hemispheres, striatum, thalamus, and medulla oblongata. The short-sleeping animals manifested elevated concentration of leu-enkephalin in the cortex and that of met-enkephalin in the striatum, medulla oblongata, and thalamus. Prolonged alcoholization under the conditions of free choice led, in the much-drinking animals, to decreased concentration of leu- and met-enkephalins in the striatum, thalamus and medulla oblongata and to increased concentration of leu-enkephalin in the cortex. The importance of leu- and met-enkephalins in the pathogenesis of chronic experimental alcoholism in rats with different alcoholic motivation is considered.     

Prevention of the formation of alcoholic motivation in rats using zinc sulfate

The experiments carried out on albino male rats have shown a decreased zinc content in the brain of active animals selected under conditions of forced swimming test, as compared to passive animals. 10-day intraperitoneal injection of biotic zinc sulfate dose (50 micrograms/kg) resulted in the prevention of alcohol motivation in active animals. There was no such effect in passive animals. The differences between basic mechanisms of alcohol motivation in different groups of animals are suggested.     

Alcohol dehydrogenase in the blood and liver of rats with different alcoholic motivation

Alcohol dehydrogenase (ADH) activity was determined by a highly sensitive method. The enzyme activity in the blood serum was similar in alcohol and water preferring rats, while ADH activity in the liver of alcohol preferring rats was higher than in water preferring rats. In rats, chronically intoxicated with ethanol, ADH activity in the liver decreased, while in the serum it was twice higher than the normal level. It is suggested that high level of blood ADH is not connected with the rate of enzyme synthesis in the liver.     

The role of the perifornix area of the hypothalamus in forming alcoholic motivation in rats

In rats with alcohol motivation on the model of water deprivation with substitution of water for 20% ethanol solution, motivatiogenic "drinking centres" of the hypothalamus initiate in response to electro- and chemostimulation (acetylcholine) behavioural reactions of search and taking of alcohol and not of water. Electrolytic ablation of "thirst centres" of the perifornical hypothalamus area in rats with a formed attraction to alcohol is accompanied by a decrease of its taking during 3-5 days of observation. Microinjections of dipsogenic peptide angiotensin II, unlike acetylcholine administration, do not initiate taking of water or alcohol, but elicit only appearance of orienting-investigating, alimentary, sexual and other behavioural reactions. It is suggested that formation of alcohol motivation in these conditions is connected with a change of neurophysiological and neurochemical properties of the hypothalamus "thirst centres" initiating an active search and taking of alcohol and not of the water in rats with experimental alcoholism.     

Effect of one-time and chronic administration of ethanol on the concentration of beta-endorphin in the brain of rats with different alcoholic motivation

The concentration of beta-endorphin was determined in the cortex of the large hemispheres, thalamus, striatum and medulla oblongata of rats with varying duration of ethanol anesthesia and after a single injection of ethanol (2.5 g/kg). The content of beta-endorphin was also measured in the brain of rats which preferred and rejected 15% ethanol during long-term (up to 10 months) alcoholization. The data obtained indicate that ethanol produces a specific effect on the endorphinergic system in different brain structures of animals predisposed to voluntary alcoholization. A possible involvement of the neuropeptide in the formation of alcohol tolerance and physical dependence is discussed.     

Isolation of sarcoma virus from noninbred rats

The data are presented on the activation of endogenous retrovirus in vaccinia virus--malignant transformed cells of rat tissue culture. Infection of the cells by Mazurenko mouse leukemia virus induced rat sarcoma virus. The latter was formed as a result of recombination of sarcoma virus-specific sequences received from the rat cells malignantly transformed by vaccinia virus and virus-helper (Mazurenko mouse leukemia virus).     

Effect of psychotropic substances on conditioned reflexes in cats after emotional excitation]

Emotional rage and fear were found to destroy the differential inhibition and the short-term memory in cats. Stelazine, haloperidol, amitriptyline, imizine, chlordiazepoxide, diazepan and benactyzine prevented these disturbances. Chlorpromazine, as well as stelazine and haloperidol in high doses, enhanced these disturbances. The tranquillizers and the antidepressants normalized the higher nervous activity at a greater dose range than neuroleptics and were more preferable for the elimination of the negative consequences of the strong emotional reactions.     

Effect of psychotropic drugs on the development of experimental gastric ulcer produced by different stress-inducing factors in rats

The anti-ulcer activity of three different doses (1/10, 1/30 and 1/90 of LD50) of imipramine, amitryptyline, chlorpromazine, amphetamine, ephedrine, chlordiazepoxide and meprobamate was studied in two types of stress-produced gastric ulcers in rats. It was found that these drugs given in doses of 1/10 or 1/30 LD50 inhibited in the same degree the development of gastric ulcer-produced by the method of Senay, in spite of differences in their psychotropic activity. On the other hand, when the method of Rossi was used for ulcer production the ulcer-preventing activity of these drugs has been varied. Thymoleptics were most effective and ataractics least effective against ulcers produced by the method of Rossi.     

Tyrosine hydroxylase activity in the brains of rats with different levels of initial alcoholic motivation

Activity and KM of hypothalamic tyrosine hydroxylase (TH) were studied in rats preliminarily tested for predisposition to high ethanol consumption. It was shown that as regards cofactor of DMPH4 enzymatic reaction, KM of hypothalamic TH of animals with an initially high alcoholic motivation is lower than that from the brain of animals rejecting alcohol, being 0.34 +/- 0.3 mM and 0.46+/- 0.10 mM, respectively. A conclusion is made that the catecholaminergic system is involved into the realization of the rewarding effects of ethanol.     

Effect of psychotropic substances on orienting-exploratory behavior after startling caused by acoustic stimulation

Frightening sound stimulation induced alarm and alertness which resulted in weakening of attention to novel environment and increasing of orienting response to the source of the frightening sound. Defense motivation occurring under these conditions failed to alter with the increase of sound loudness. Tranquilizers (diazepam, chlordiazepoxide, benatyzine), antidepressants (amytriptiline, imipramine) and some neuroleptics (trifluoperazine, haloperidol) in a low doze prevented these disturbances. High doses of pentobarbital, chlorpromazine, as well as trifluoperazine and haloperidol did not prevent the mentioned consequences of emotional excitation.     

Effect of psychotropic substances on dopamine uptake by synaptosomes and glial cells]

Dophamine-H3 uptake by synaptosomes and glial cells of the cerebral cortex in rabbits and by the synaptosomes of the cerebral cortex in rats was studied. KM value of the dophamine-H3 uptake was found to be the same (0.075 +/- +/- 0.01 micrometer) in case of synaptosomes and glial cells. The rate of dophamine-H3 uptake by the rabbit cerebral cortex synaptosomes was twice that of the gial cells (as compared by protein). Among the psychotropic agents studied the most active symaptosome uptake inhibitors were phenamine and cocaine; they were less active in respect to glial uptake. Both types of uptake were inhibited by neuroleptics and antidepressants to the same degree. Results of this work conformed to the view on the participation of the strial dophaminergic link in the action mechanism of psychostimulants.     

Effect of taurine on alcoholic liver disease in rats

To investigate the effect of taurine on alcoholic liver disease in rats, male Wistar rats were administered alcohol intragastrically for 3 months. The effect of β-alanine-mediated taurine depletion and taurine administration on the development of alcoholic liver disease was examined. It was found that taurine administration produced lower levels of aspartate aminotransferase and alkaline aminotransferase than that of the untreated group. In addition, the levels of hepatic total protein, glutathione and superoxide dismutase were higher in the taurine treated groups than those in the untreated control or the taurine depleted groups, while hepatic malondialdehyde content exhibited the negative effect. Moreover, the concentrations of hepatic hydroxyproline, serum hyaluronic acid, interleukin-2, interleukin-6, tumor necrosis factor-α and laminin were all decreased in the taurine treated groups. The pathological changes showed that the percentage of fatty degeneration and inflammation in the taurine groups were lower than that of the control, taurine depleted and automatic recovery groups. These in vivo findings demonstrate that hepatic disease caused by chronic alcohol consumption can be prevented and cured by administration of taurine.     

Relation of alcoholic motivation to the functional state of the emotive zones of the brain in rats

Reactions of neurones pair of positive and negative emotiogenic hypothalamus zones to electrocutaneous stimulation and to intraperitoneal administration of ethanol solution (2 g/kg) were studied in outbred male rats with previously determined attitude to alcohol. In animals who preferred alcohol the neurones of the negative zone were significantly more reactive, and in animals who preferred water the neurones of the positive zone were more reactive. In both studied groups of rats, in most cases ethanol had an inhibitory influence on impulse activity of negative zone neurones, but it acted differently on positive zone neurones: in most cases it intensified neurones impulse activity in rats preferring alcohol and significantly inhibited it in animals rejecting alcohol.