Hormonal control of interdigestive motor cycles of canine proximal stomach

Abstract

Whether the interdigestive motor cycles of the canine proximal stomach are hormonally regulated was studied. In 4 dogs, a pouch of gastric fundus and orad corpus was completely, extrinsically denervated by autotransplanting it in the left pelvis. Electrodes were implanted on the pouch, the main stomach and the proximal small intestine. After recovery, intraluminal pressure was measured in the pouch during fasting, whereas electrical activity was recorded concurrently from the pouch, main stomach and small intestine. Pouch motility was cyclical, with bursts of large amplitude contractions occurring at intervals of about 1.8 h (108 .+-. 8; mean .+-. SE). The bursts of large amplitude contractions were found in the pouch at the same time that bursts of intense action potential activity were detected in the main stomach and duodenum. The interval between pouch bursts (108 .+-. 8 min) did not differ from the interval between duodenal bursts (107 .+-. 1 min, P > 0.1), and the end of the pouch bursts preceded the end of the duodenal bursts by only 1 .+-. 1 min. Feeding 100 g liver abolished pouch and duodenal bursts and decreased integrated pouch pressure from 11 .+-. 2 cmH2O .cntdot. min before eating to 3 .+-. 1 cmH2O .cntdot. min by 20 min after eating. The interdigestive motor cycles of the canine proximal stomach and their abolition by feeding are apparently hormonally regulated.