Human fasting and postprandial sphincter of Oddi motility.

Sphincter of Oddi motility was evaluated in post-cholecystectomy patients with indwelling T tubes during fasting and after feeding. A triple-lumen catheter was positioned to record from the sphincter of Oddi and duodenum. The sphincter of Oddi was characterized by phasic contractions independent of duodenal contractions. During fasting duodenal wave frequency exhibited four phases, whereas only two phases could be identified from the sphincter of Oddi. A prolonged phase A in the sphincter of Oddi corresponded to duodenal phases I, II and IV. A short phase B in the sphincter of Oddi just preceded the onset of duodenal phase III and was temporally related to it. Sphincter of Oddi basal pressure increased during duodenal phases III and IV. After ingestion of food, sphincter of Oddi basal pressure, wave amplitude and duration decreased, but the frequency remained unchanged. Conversely, duodenal frequency increased but there was no change in amplitude. Thus, the human sphincter of Oddi and duodenum exhibited independent motility demonstrating distinct phases during the interdigestive period. After food, sphincter of Oddi motility altered in a manner which would facilitate the passive flow of fluid into the duodenum.