Effect Of Stenosis Of The Sphincter Of Oddi On Biliary Dynamics And Myoelectric Activities In Dogs

Background:The spincter of Oddi (SO) is a complex, valve-like, neuromuscular structure located at the junction of the bile and pancreatic ducts with the duodenum,it is the common outlet of bile and pancreatic fluid. Sphincter of Oddi dysfunction (SOD) is the main cause of biliary pain after cholecystectomy and of endoscopic spincterotomy (EST) and cholangiojejunos tomy for cholelithiasis patients, which perplex the patients and doctors. Two types of SOD have been recently proposed: SO stenosis and SO dyskinesia by most scholars. The former refers to a structural alteration of the sphincter, in which there is a narrowing of part or the whole sphincter, probably due to an inflammatory process from pancreatitis or injury from gallstone migration through the papilla with subsequent fibrosis. In contrast, the latter refers to a primary motor abnormality of the SO, which may result in a spasm, hypertrophy or denervation of SO. The complete structure of the SO and normal motor activities is very important for adjustment of biliary secretion and prevention of biliary duct infection. With the development of SO manometry (SOM) and SO electromyography (SOE), the researchers gradually focus on how to differentiate SO stenosis and SO dyskinesia. For this reason, we established a stenosis model in mongrel dogs to explore effect of Stenosis of the sphincter of Oddi on biliary dynamics and myoelectric activities.Objective:To established a stenosis model in mongrel dogs and observe the effect of Stenosis of the sphincter of Oddi on biliary dynamics and myoelectric activities, and try to find a reasonable mechanism to clinical practice.Methods:After fasting for 16-18h, the adult mongrel dogs were anesthetized and performed ultraSOnograph to determine the size of the common bile duct (CBD). In the experimental group, the dogs'SO accepted mechanical damage by operation, while in the control group, only sham operation was done. All dogs accepted ultrasonograph to determine the size of CBD again and sphincter of Oddi manometry (SOM) and SO electromyography (SOE) to detect biliary dynamics and myoelectric activities at postoperative 4 weeks. Serum examination of liver function was obtained periodicly. After the second operation, SO specimens were biopsy for pathology analysis. In the end, we analyze the data obtained by SOM and SOE with specialized software.Result:In the experimental group,liver function such as TBIL,DBIL,GGT,ALP and the size of CBD by ultrasonograph were higher than preoperative, the SO fibrosis significantly in pathology, However in the control group, there were no obvious change. Compared the experimental with the control group, the basal pressure of CBD and SO was increased significantly, the frequency of SO contraction was increased, whereas the SO amplitude was decreased. And compared the experimental with the control group, the voltage amplitude of slow waves and spikes decreased significantly in myoelectric activities.Conclusion:The model ofstenosis of SO was established successfully and the stenosis of SO caused changes of biliary dynamics and myoelectric activities significantly...