Omental Adipose' Effect On The Bile Duct Stricture Scar And The Biliary-enteric Anastomosis In The Experimental Study

Objective To establish a animal model of bile duct strictures by electrocautery injury and a animal model of cholecystojejunostomy in Japanese rabbits, and to observe the effect of omental adipose'on the Bile duct stricture scar and the biliary-enteric anastomosis by the two model.Methods Part 1:10 Japanese rabbits were randomly divided into two groups, electrocautery injury of bile duct and electrocautery injury of skin and hepatobiliary anatomy were applied respectively. Part 2:25 Japanese rabbits were randomly divided into three groups, electrocautery injury of bile duct(A group n=10), electrocautery injury of bile duct and the place of bile duct injury by Omental wrap(B group n=10), sham operation(C group n=5) were applied respectively. The general condition and survival of animals were observed after operation. The bile duct stenosis and the omental adipose'effect were observed by MRI, gross morphology and Stained by HE 30 days after surgery.25 Japanese rabbits were randomly divided into three groups, cholecystojejunostomy (D group n=10), cholecystojejunostomy and the biliary-enteric anastomosis by Omental wrap (E group n=10), sham operation(F group n=5) were applied respectively. The general condition and survival of animals were observed after operation. The biliary-enteric anastomosis and the omental adipose'effect were observed by gross morphology and Stained by HE 60 days after surgery.Results Part 1:in the same electrocautery time(0.5s), it was little electrocautery effect under the 5W; It was large damage range and degree of injury more than 25W, it was ease to bile duct necrosis and bile leakage; It was good effect between 10W to 20W. The Japanese rabbits'liver have four lobes, each lobe have their bile duct, trefoil merged into a liver bile duct down, and then with the fourth lobe of the liver's bile ducts unite to form the common bile duct, the bile ducts are small(Diameter of 0.5mm～2mm), the common bile duct is shorter, the gallbladder is relatively large, about 2.5cm×1cm×1cm. Part 2:One animal bile leakage occurred in A group, no bile leakage occurred in the both of B group and C group. The Bile duct stricture and the bile duct cholangiectasis were observed by MRI and gross morphology in the both of A group and B group, but there was no change in the sham operation group. The Bile duct fibrosis were observed by HE in the both of A group and B group Adipose cells can growth into the collagen fiber organization and were surrounded by dense collagen fibers in B group. Adipose tissue and bile duct scar tissue collagen fibers blend with each other well, the biliary-enteric anastomosis stricture and the regurgitation were observed by gross morphology in the both of D group and E group, but there was no change in the sham operation group. The biliary-enteric anastomosis fibrosis were observed by HE in the both of D group and E group. Adipose cells can growth into the collagen fiber organization and were surrounded by dense collagen fibers in D group. Adipose tissue and bile duct scar tissue collagen fibers blend with each other well.Conclusions 1. Each liver lobe have their bile duct in the Japanese rabbits. There was little effect of liver function to injury a lobe of the liver bile duct. It was suitable for establishing a animal model of bile duct strictures by electrocautery injury.2. The Japanese rabbit'gallbladder is large. The gallbladder diameter was similar to human bile duct diameter after expansion. It was suitable for establishing a animal model of cholecystojejunostomy.3. Electrocautery power of bile duct was 10W to 20W, at the time of 0.5s.4. The model of bile duct strictures by electrocautery injury was successfully established in Japanese rabbits. There is feasible for empirical study of bile duct stricture scar.5. The model of cholecystojejunostomy was successfully established in Japanese rabbits. There is feasible for empirical study of complications of biliary-enteric anastomosis.6. Omental adipose tissue play a role of fusion and plugging in the bile duct stricture scar and the biliary-enteric anastomosis. Omental adipose tissues provides a experimental basis for the prevention and treatment of bile duct stricture scar and biliary-enteric anastomosis stenosis.