[EFFECT OF CITOFLAVIN ON THE PARAMETERS OF LIPID PEROXIDATION IN BLOOD PLASMA OF RATS UNDER COLD STRESS CONDITIONS.]

The possibility of correcting free radical oxidation of lipid membranes by the administration of cytoflavin was experimentally studied in rats. It is established that daily cold exposure for 3 h leads to increase in the level of lipid hydroperoxides, diene conjugates, and malonic dialdehyde on the background of decrease in activity of the antioxidant system in the blood of experimental animals. The introduction of cytoflavin (100 mg/kg, i.p.) for 21 day immediately prior to cold exposure leads to reliable (p < 0.05) decrease in the blood level of lipid hydroperoxides (by 13 - 21%), diene conjugates (by 24 - 25%), and malonic dialdehyde (by 20 - 33%) in comparison to rats of the control group. Analysis of the effect of cytoflavin on activity of the antioxidant system components showed that the level of ceruloplasmin and vitamin E in the blood of animals was reliably (p < 0.05) higher by 10 - 33% than analogous indicator in rats of the control group. Thus, the application of cytoflavin under conditions of long-term influence of cold on the organism of animals leads to stabilization of the processes of lipid peroxidation on the background of increased activity of the blood antioxidant system.

[Role of the hypothalamus in originating disorders of exploratory behavior and learning in rats with excised nuclei of the locus coeruleus]. / Rol' gipotalamusa v geneze rasstroistv issledovatel'skogo povedeniia i obucheniia u krys s razrushennymi iadrami locus coeruleus.

Open-field behaviour and emotionally differently reinforced learning were studied in male Wistar rats with bilaterally ablated Locus coeruleus. Histochemical analysis of the hypothalamic structures was carried out. Decrease of investigating activity and attention was found as well as disturbances of learning with emotionally-negative (painful) reinforcement. By means of histochemical methods, fluorescence characteristic for catecholamines was found to decrease sharply in paraventricular and supraoptic hypothalamic nuclei, eminentia medialis and the posterior lobe of the hypophysis.

[Learning of animals during adaptation to altitude and its relations with serotonin metabolism in the brain]. / Obuchenie zhivotnykh v usloviiakh adaptatsii k vysokogor'iu i ego sviaz's obmenom serotonina mozga.

The influence of high altitude (3 200 m) on learning was studied on 104 non-linear male rats weighing 120 to 140 g, along with biochemical analysis of serotonin content (5-HT) and noradrenaline (NA) in brain structures. A drastic deterioration in the animals' learning has been established in conditions of high altitude, both with alimentary and pain reinforcement attended with a considerable suppression of the 5-HT and NA brain systems activity. Systematic administration of 5-HTP resulting in an enhanced serotonin level in the cortex and the caudal part of the brainstem, improved the learning process, regardless of the emotional sign of the reinforcing stimulus. The prospect, is being substantiated, of evolving methods preventing pathological implications of external influences of high altitudes on the organism by means of pharmacological actions on monoamines' metabolism.

[Effect of damage to the serotonin- and noradrenergic systems of the brain on alimentary and defensive conditioned reflexes in rats]. / Vliianie povrezhdeniia serotonin- i noradrenicheskoi sistem mozga na pishchevye i oboronitel'nye uslovnye refleksy u krys.

A study was made on 79 Wistar male rats of the influence of destruction of single nuclei in the brain serotonin- and noradrenergic systems on their learning with alimentary and pain reinforcements. Electrolytic lesion of the raphe dorsal and medial nuclei hindered the formation of alimentary conditioned reflexes, while facilitating the elaboration of a conditioned active avoidance reaction. Destruction of the locus coeruleus was attended with improved alimentary learning, while the elaboration of conditioned active avoidance reaction proved to be more difficult as compared with that in the control animals. A conclusion is drawn that the nature of the influence of local ablation of individual nuclei in the brain serotonin- and noradrenergic systems on animals' learning is determined by the emotional sign of the reinforcing stimulus.