心筋内カテコラミンに関する研究 ： 急性心筋虚血・再潅流時の心血行動態，血中および組織内カテコラミン

Abstract

A study was performed on anesthetized dogs to investigate the changes in hemodynamics, plasma catecholamine concentrations and catecholamine stores in the heart muscle during experimental acute myocardial ischemia and reperfusion. Ligation of the left anterior descending coronary artery produced a decrease in cardiac output (CO) and rises in pulmonary artery pressure (PAP), pulmonary capillary wedge pressure (PCWP) and right atrial pressure (RAP). Obstruction and reperfusion of the coronary artery did not alter mean aortic blood pressure (ABP) or heart rate (HR) in the course of the experiment. Catecholamine stores in the heart muscle were significantly lower in the ischemic zone than in the non-ischemic zone of the reperfused and non-reperfused heart. Marked increases in noradrenaline and adrenaline concentrations in aortic and coronary sinus blood after ligation were observed, with the degree of increase in noradrenaline concentration higher in coronary sinus blood than in aortic blood. The elevated noradrenaline and adrenaline concentrations in coronary sinus blood persisted after reperfusion, while noradrenaline and adrenaline concentrations in the aortic blood tended to decline to the original levels. The decline in catecholamine stores in the ischemic tissue is suspected to be due mainly to degeneration of the sympathetic nerve fibers distributed in the heart muscle. This release of catecholamines from the nerve fibers may account for the increase of catecholamines in coronary sinus blood and hemodynamic changes.