[Effect of emotional-pain stress on myocardial contraction in prolonged hypokinesia].

Prolonged restriction of rat mobility resulting in stoppage of the body and heart mass growth was accompanied by the increased contraction and relaxation velocity of isolated papillary muscles. Absolute values of the poststressor decrease in the main parameters of myocardial contractility in prolonged hypokinesia-exposed animals did not substantially differ from those in controls. The resultant functional significance of such a depression was less dangerous. The data suggest that the increased resistance of the animal body, particularly of the heart muscle to the damaging effect of acute stress in prolonged hypokinesia is an essentially stressful state.