It was established in experiments on anesthetized dogs with a closed thorax that injection of anticardiac cytotoxix serum into one of the main branches of the left coronary artery is accompanied by regional disturbances of energy metabolism, manifested by a decrease in ATP, ADP, AMP and glycogen content, and in the contractility of a injured area of the left ventricle. Undamaged myocardium of the left and right ventricles showed a compensatory hyperfunction and an increased level of noradrenaline. The energy metabolism parameters of undamaged cardiac area do not undergo any material changes.