Abstract
The present study was made to investigate the details of bile flow mechanism into the duodenum in man.
For this purpose nineteen patients with gallstone disease operated upon in our department were studied. After cholecystectomy and/or choledocholithotomy, a metalic catheter was inserted into the common bile duct toward the duodenum to identify the choledochoduodenal junction, the muscle of Oddi. A bipolar Ag-AgCl needle electrode was sewn in the muscle of Oddi. Another electrode was implanted into the anterior wall of the duodenum. T-tube was set in the common bile duct. The action potentials of these muscles were recorded with a 2-channel DC amplifier with ink writers for 5 to 17 days after operation. At the same time, the action potentials displayed on a cathode-ray oscilloscope and biliary radiogram on an image intensifier were simultaneously recorded on the cine film.
The results obtained are as follows:
1) Electrical activities of the Oddi's muscle and the duodenum were recorded almost simultaneously, but they were different in the detailed discharge pattern. 2) When an electrical stimulation was given to the muscle of Oddi, the action potential was markedly accelerated and the intraductal pressure was elevated, but no change of the discharge pattern was seen in the duodenum. Reversely, when the same stimulation was given to the duodenum, the electrical activity was markedly accelerated in the duodenum, but the muscle of Oddi was not influenced and also the intraductal pressure was not elevated. 3) Bile flow was interrupted at the terminal portion of the common bile duct when electrical activity of the muscle of Oddi was observed. 4) When bile was poured into the duodenum, electrical activity of the muscle of Oddi was not observed. 5) Bile flow was not interrupted by the electrical activity of the duodenal wall muscle.
From the above observations the author concluded that the muscle of Oddi had a sphincteric mechanism and acted independently of the activity of the duodenal wall muscle.
