Effects Of Ischemic Preconditioning On Ischemia-reperfusion Tissue Of Bile Duct In Rat

Objective To observe the protection effects of ischemic preconditioning on ischemia-reperfusion tissue injury of bile duct in rat.Methods: Twenty four SD rats were randomly divided into three groups, sham operation group(SO), ischemic reperfusion group(IR) and ischemic preconditioning group(IP), There were eight rats in each group. In IR group, rats were given abdominal anesthesia, abdominal incision was made after sterilizing. Perihepatic ligament was dissociated and liver collateral vessels were excised. Vascular blockage made for twenty minutes and then reperfusion for one hour. On the basis of IR group, 5 minutes blockage and 5minutes reperfusion was made before the formal blockage and reperfusion in IP group. All other methods remain similar to IR group. In SO group, rats were given abdominal anesthesia, abdominal incision was made after sterilizing. No blood blockage and no vessel excision made either. Experiment time kept same as IP group. Afer one hour reperfusion, bile duct tissue of rats were sampled to be observed with electron mictoscope and the level of SOD were measured, the bile of rats were collected and measured in r-GT, the blood samples of rats were taken and then levels of alanine transaminase and aspartate transaminase in serum were measured, at last, the rats were killed.Results: In SO group, bile duct epithelial cells are mormal, nucleus size is noral. mitochondria distribution is unifoum, size is normal, matrix is uniform, double membrane structure and cristae are clear. In IR group, bile duct epithelial cells were swelling obviously, mitochondria distended, cristae collapsed and matrix appeared like frosted glass. Compare with IR group, epithelial cells swelling is comparatively light in IP group, matrix is not so uniform, cristae are comparatively blur. Tissue pathomorphology shows that compare with SO group, though the injury of liver and bile duct were observed in both IR group and IP group, the injury of liver and bile duct in the IR group was more serious than that in the IP group. In the IR group, the level of SOD(u/mgprot) in bile duct tissue was(161.71±10.34), which was significantly lower than that in SO group(181.19±11.73) and IP group(175.23±6.48), there were difference between IR group and SO group and IP group,(P﹤0.05), there were no difference between IP group and SO group,(P﹥0.05). The level of r-GT(Iu/L) in bile was (32.05±14.96) in the IR group, and (11.32±7.25) in SO group, and (17.63±7.26) in IP group, there were difference between IR group and SO group and IP group,(P﹤0.05), there were no difference between IP group and SO group,(P﹥0.05). The level of ALT(u/L) and AST(u/L) in serum was (240.00±102.95) and (558.31±236.01) in IR group, and (97.50±47.02),(145.38±65.32 ) in SO goup, and (239.65±91.72),(372.70±152.59) IP group, there were difference between IR group and SO group,(P﹤0.05), there were no difference between IP group and SO group,(P﹥0.05).Conclusion: The ischemia-preconditioning with five minuts can protect ischemia-reperfusion tissue of bile duct in rat.