PURPOSE: To observe the effect of cholecystectomy on the changes of motion pattern of Beagle dogs' sphincter of Oddi (SO), and investigate the modulatory role of nitric oxide (NO) and cholecystokinin (CCK) in the regulation of SO.METHODS: Pressure of common bile duct, SO motility, response to bolus injections of cholecystokinin (CCK, 20 ng/kg and 100 ng/kg), basal pressure (BP) and phasic contraction amplitude (PCA) were measured respectively by manometry in six Beagle dogs before and after cholecystectomy.RESULTS: After cholecystectomy, the pressure and diameter of common bile ducts (CBD) was significantly increased (p<0.01); BP and phasic contraction frequency (PCF) were also increased, however, no significant differences were found between the two groups; the SO motilities was not significantly changed. The relaxation responded to physiological dose of CCK (20ng/kg) was decreased, while bolus-dose of CCK (100ng/kg) induced rapid contractions and decreased PCA after cholecystectomy. The regulation pattern of SO pressure modulated by NO and its inhibitor had changed after cholecystectomy.CONCLUSION: After cholecystectomy in Beagle dogs, no obviously change of motion pattern of SO was observed through self-compensation, but these compensations may lead to some changes of regulation pattern of CCK and NO on SO.

PURPOSE: Natural orifice transluminal endoscopic surgery (NOTES) is a new technique. This study describes our initial experience of NOTES and investigates the feasibility of transumbilical endoscopic cholecystectomy (TUEC). METHODS: Eight domestic pigs were submitted to TUEC. After establishment of pneumoperitoneum, a bi-channel endoscope was placed through an infra-umbilical trocar. The gallbladder fundus was lifted by a grasper. The cystic duct and artery was dissected with a flexible hook and clipped by a clip fixing device. The specimen was extracted through the infra-umbilical trocar. RESULTS: The mean operation time was 114 minutes, ranging from 75 to 155 minutes. All the gallbladders were removed successfully. There was one case of subtotal resection, two cases of bleeding and three cases of bile leakage. CONCLUSION: Transumbilical endoscopic cholecystectomy is feasible although it needs more support of experiments and techniques before being applied on human subjects.