Distribution of Cardiac Sympathetic Nerves

抄録

1. The norepinephrine concentration was determined fluorimetrically in various portions of the heart of 30 unilaterally sympathectomized dogs. The operation was performed on the left side in one half of the dogs and on the right side in the other half. 2. The norepinephrine concentration showed a significantly marked decrease in both atria, the right ventricle, the ventricular septum, and the anterior portion of the left ventricle following unilateral cervical sympathectomy on either side. It exhibited also a marked decrease in the postero-lateral portion of the left ventricle following left cervical sympathectomy. It was not affected, however, in the same portion of the left ventricle by right cervical sympathectomy. 3. From the results above mentioned it was postulated that the postero-lateral portion of the left ventricle might be supplied exclusively by the left cardiac sympathetic nerve and that the other portions of the heart might be innervated bilaterally with some unilateral preponderance. The right ventricle was assumed to be supplied predominantly by the right cervical, sympathetic nerve, while the anterior portion of the left ventricle and the ventricular septum were considered to be innervated predominantly by the left nerve. 4. It seems that the cardiac sympathetic nerve of the intact side may compensate the function of the corresponding nerve of the other side where unilateral cervical sympathectomy has been performed. This presumption has been made, since the norepinephrine concentration showed a slight tendency toward the preoperative level 28-30 days following unilateral cardiac sympathectomy.