[The mechanisms of the neurotropic action of bromantan]. / Mekhanizmy neirotropnogo deistviia bromantana.

The main components of bromantan central neurotropic effect is its dopamine-positive activity: antagonism (5 mg/kg) to the effects of neuroleptics in rats, blocking (50 microM) of dopamine synaptosomal capture, and a complicated in structure influence on the serotoninergic mediator systems--inhibition of neuronal capture of serotonin (50 microM), behavior responses to 5-hydroxytryptophan (1-20 mg/kg) in mice, decrease in the mediator content in intact rat brain when administered in doses lower than 5 mg/kg, and the absence of this parameter with the use of higher doses. The central noradrenergic effect of the drug is less expressed: blocking of the synaptosomal capture of norepinephrine in higher (more than 500 microM) concentrations), and absence of an effect, in distinction from sydnocarb, 1-5 mg/kg, on the mediator content in intact rat brain. The drug (1-50 mg/kg, intravenously) has no effect on neuro-muscular transmission in cats and in higher doses (30-600 mg/kg) inhibits to a certain degree the central effects of nicotine and arecoline.

[Correlations between the indices of the state of the sympathetic-adrenal and of the hypophyseal-adrenal systems and the level of insulin in horses under various exposures]. / O korreliatsionnykh vzaimosviaziakh mezhdu pokazateliami sostoianiia simpatiko-adrenalovoi, gipofizarno-nadpochechnikovoi sistem i urovnem insulina u loshadei pri razlichnykh vozdeistviiakh.

The content of adrenaline, noradrenaline, ACTH, cortisol and insulin in the blood and excretion of catecholamines with urine were studied in horses after physical and emotional exposures. The highest degree of the sympathoadrenal system (SAS) and hypophysioadrenal system (HAS) activation followed by the insulin content decrease was observed after training. The known emotional exposure (the noise of hyppodrome) astivated both parts of SAS and HAS. The unknown emotional experience (electronic music) produced a strong adrenal medullar reaction. Analysis of the correlations showed that the initial background hormonal level predetermines the further activation of the system exposed to stressful situations. The reciprocal relations between the hormonal and mediator parts of SAS at rest are transformed to common activation under training. The level of the activity of one part of SAS monitors the other one. A relationship was established between SAS and HAS as well as between insulin and catecholamine content under physical and emotional exposures.

[Catecholamine metabolism during adaptation to muscular activity]. / Obmen katekholaminov pri adaptatsii k myshechnoi deiatel'nosti

In rats, an increased O-methylation in the brain, heart, liver, and in the m. gastrocnemius as well as an increased intensity of oxidative desamination in the liver were revealed after muscular training and administration of retabolile. After additional 70-min swimming, in intact rats the MAO activity was raised in the liver, and the intensity of O-methylation - in the muscle and the heart. In rats adapted to muscular training, no increase of O-methylation in the heart or MAO activity in the liver was observed which may be regarded as an adaptive hypometabolic reaction of the organism for a more "ecomonic" usage of the catecholamines. An increase of the catecholamines contents was revealed in adrenals of the rats after training and retabolile administration. The 70-min swimming obviously suppressed the catecholamines synthesis in the rat adrenals. The synthetic activity of the adrenals in trained animals was also decreased, although insignificantly, which resulted from the preliminary adaptation of the organism to muscular activity.