ABSTRACT
Experiments on chemically sympathectomized rats have revealed a double effect of the sympathetic nervous system on compensation and adaptation of heart function and reparative regeneration in myocardial infarction. It has been established that if the sympathetic influences are excluded, the elements of the connective tissue are activated, which leads to myocardial infarction healing at a shorter period of time. At the same time it has been demonstrated that sympathectomy inhibits the development of the compensatory reactions and limits adaptation possibilities of the heart.
Subject(s)
Heart/innervation , Myocardial Infarction/physiopathology , Sympathetic Nervous System/physiopathology , Animals , Heart/physiopathology , Male , Rats , Rats, Inbred StrainsABSTRACT
Experiments on 142 Wistar male rats were made to study the effect of chemical desympathization on functional and structural changes in the heart during acute myocardial ischemia produced by ligation of the anterior descending branch of the left coronary artery. In the desympathized rats with acute myocardial ischemia, arrhythmias occurred in a less number of cases and were less severe. One day after the artery occlusion the decrease in myocardial contractility was less considerable than in the control animals. More rapid localization of the ischemic focus was found to occur in the desympathized myocardium. The pattern of changes in lipid metabolism in the desympathized and in normally innervated heart was different: in the desympathized heart accumulation of neutral fat was observed while in the normal one acid lipids. It is concluded that different pattern of functional and structural changes in the myocardium of the normal and desympathized animal is determined by the status of the heart sympathetic nervous system, namely by a decrease or elimination of the pathogenic action on the myocardium of noradrenaline which is released in high concentrations because of sharp stimulation of the sympathoadrenal system.
