Jiro Kaneko

Studies on the control of coronary circulation Part I. The effect of the stimulation of the nerves on the coronary circulation. Part II. The humoral effect on the coronary circulation

Abstract 1. 1. A study was made of the coronary vasodilatative effects of coronary venous blood samples obtained following the stimulation of the sympathetic and vagal nerves, and of norepinephrine, acetylcholine, and ATP. 2. 2. In the coronary venous blood samples, obtained either during or 15 seconds after the stimulation of the sympathetic nerves, some vasodilatative substances were demonstrated. They may play one of the important roles in sympathetic coronary vasodilatation. The exact nature of the vasodilatative substances are unknown, but they may be the metabolites released following the sympathetic stimulation. 3. 3. The coronary vasodilatative effect of norepinephrine differs in nature from that of acetylcholine, ATP, and effective coronary venous blood. It may result mainly from hemodynamic and metabolic action due to the modification of the heart. The action of norepinephrine on coronary vessels seems to be identical with that of the sympathetic nerves.