[Study on the catecholamine-containing fibers in the vagus].

To clarify the nature and the origin of the catecholamine in the vagus, a quantitative estimation of dopamine, norepinephrine and epinephrine in the human abdomen, canine cervical and supradiaphragmatic vagus was performed. The human abdominal vagus was obtained during surgical operations. The canine cervical vagus was taken out with superior cervical ganglion and its branch between superior cervical ganglion and vagal trunk. The canine supradiaphragmatic vagus was ligated doubly. The control segment (between two ligatures) was removed immediately after the ligations. The proximal segment (1 cm above the cranial ligature) and the distal segment (1 cm below the caudal ligature) were taken out four hours after the ligations. The human and canine vagus contained dopamine and norepinephrine not epinephrine. The canine cervical vagus, which was cranial part to the unite of the branch from the superior cervical ganglion, contained dopamine and norepinephrine. Dopamine and norepinephrine levels in the proximal segment was greater than that in the control segment. Dopamine and norepinephrine levels in the distal segment was less than that in the control segment. Based on these results, it is concluded that: (1) catecholamine s in the human and canine vagus are dopamine and norepinephrine not epinephrine; (2) the catecholamine-containing fibers in the canine vagus originate partially in the vagal trunk; (3) dopamine and norepinephrine may be transported distally in the canine vagus.