[Effect of hypokinesia and muscle training on catecholamine levels of the myocardium of rats in postnatal ontogeny].

Following muscular training and hypokinesia in postnatal ontogenesis (10 weeks) rats were examined by fluorometry for the content of catecholamines at rest and after extreme exertion (swimming). Regular muscular training led to an increase in catecholamine concentration in the myocardium. Hypokinesia decelerated catecholamine accumulation by the myocardium. A single extreme swimming exercise brought about a decrease in catecholamine concentration in the myocardium. The minimal adrenaline concentration was the same, being equal to 0.04 microgram/g crude tissue whatever the age and locomotion pattern.