Abstract
Electromyograms of the duodenum in rabbits were recorded from the four points, namely the choledochoduodenal junction, other point of the duodenum on the junctional level, oral and anal points of the duodenum. Further, circular and longitudinal muscles were incised, and electromyograms were recorded.
1. In healthy rabbits, action currents taken from each point showed no difference in number and amplitude of bursts, but slight difference was observed in intervals of bursts.
2. By incision of the circular muscles, only number of bursts remarkably decreased at the choledochoduodenal junction, however, amplitude of spikes slightly decreased and interval inbetween bursts did not show so remarkable changes at other points of the duodenum.
3. By incision of the longitudinal muscles, amplitude of spikes decreased in every point, but number of spikes and rhythm of bursts showed no remarkable changes.
Action currents of every point were accelerated by administration of vagostigmin, imidarine and secretin, but were inhibited by atropine.
It is thought that action of choledochoduodenal junction is not influenced by the duodenal muscle, and electromyogram at choledochoduodenal junction is remarkably influenced by incision of circular muscles of the duodenum, and electromyographical changes of every point is not so remarkable by incision of longitudinal muscles.
It is unable to conclude whether the movement of choledochoduodenal junction is functionally dependent or independent from the duodenal wall muscles.
