[Prevention of heart contractile disorders in experimental infarct by using preliminary adaptation to stress exposure and opioid peptides].

Preliminary adaptation to brief immobilization stresses was shown to reduce impairments of the contractile function of the left ventricle in an experimental myocardial infarction both under conditions of physiological rest and following the short blocking of the aorta. This protective effect is occasioned, along with other factors, by the prevention of the stressory damage to the non-ischemic portions of the heart. The same adaptation increased the levels of enkephalins and beta-endorphin in the cerebral and adrenal structures. The preliminary administration of beta-endorphin prior to the stimulation of an experimental infarction considerably prevented stressory disorders of the contractile function of the right atrium.