A Factor Condition­ing the Inhibitory Response of the Intestinal Motility to the Peripheral Stimulation of the Cervical Vagus Nerves

Recording the motility of the stomach as well as the small intestine by the balloon method in the dogs decerebrated and unanesthetized, we found a factor conditioning the inhibitory effect of the intestinal motility to the stimulation of the perpheral cut-end of cervical vagus nerves. The results may be summarized as follows: (1) The stimulation of the peripheral cut-end of the cervical vagus nerve frequently produces the yarious patterns and degrees of inhibition of the intestinal motility of the stomach as well as of the small intestine. (2) The inhibitory effect still appears after the severing of the vagus nerves at the caudal end of the esophagus, but is obliterated and reversed to the augmentory when the splanchnic nerves are bilaterally severed. (3) The cause of the inhibition is attributable to the strong excitation of the intestinal inhibitory centers brought about by the central stimulating action of the anoxemia resulting from the stimulation of the cervical vagus nerves, and the reversal of the response is due to the peripheral stimulating action of the anoxemia upon the intestinal muscles, its central action being excluded from the action on the intestine by the severing of the splanchnic nerves.