The Empirical Study On The Protection Of Ischemic Postconditioning For The Graft In Rats After Reduced-Size Liver Transplantation

Partâ… The Operation of 60%Reduced-Size Liver Transplantation (RSLT)in RatsObjective:To study the operation technique of 60%reduced-size liver transplantation(RSLT)in rats and to provide a reliable model for the study of RSLT.Methods:50 cases of 60%RSLT operations based on the modified Kamada cuff technique were performed according to the reports of Omura.Results:In 28 cases of formal operations,the donor liver harvesting time was 25±5min,the bench-work preparation time was 15±3min,the anhepatic time was 20±2min and the successful rate was 85.7%(24/28)after the liver grafts undergoing 0-1min of warm ischemia.Conclusion:The rats' 60%RSLT model performed based on the modified Kamada cuff technique and report of Omura is reliable to the study of experimental and clinical problems of RSLT.Partâ…¡The Protection Effect of Ischemic Postconditioning on Ischemic Reperfusion Injury of Liver Graft after Reduced-Size Liver Transplantation in RatsObjective:To verification the protection effect of ischemic postconditioning(IPO)on ischemic reperfusion injury of liver graft after reduced-size liver transplantation(RSLT)in rats and to study the mechanisms roughly.Methods:Male Spraque-Dawley rats were used as donors and recipients of RSLT and were divided into ischemic reperfusion injury group(IRI group),ischemic postconditioning 1 group(IPO 1 group),IPO 2 group and IPO 3 group according to whether IPO was performed and the style of the IPO before the liver graft was reperfused sufficiently.The animals were killed at 2h and 6h after reperfusion.Plasma samples were collected for ALT and AST test.Fresh liver tissues were collected to detect the content of myeloperoxidase(MPO),superoxide dismutase (SOD)and malonaldehyde(MDA).The histological changes of hepatic tissue were examined after hematoxylin and eosin(HE)stains.And the expressions of intercellular adhesion molecule-1(ICAM-1)were examined by immunohistochemistry stain methods.Results:The serum levels of ALT and AST and the hepatic content of MPO and MDA in IPO 2 group and IPO 3 group were lower than IRI group and IPO 1 group significantly(p＜0.05)at 2h and 6h after reperfusion.The hepatic content of SOD in IPO 2 group and IPO 3 group were lower than IRI group and IPO 1 group significantly(p＜0.05)at 2h and 6h after reperfusion.The ICAM-1 expression in IPO 2 group and IPO 3 group were lower than IRI group and IPO 1 group significantly(p＜0.05)at 6h after reperfusion.All index had no significantly different between IPO 2 group and IPO 3 group,neither between IRI group and IPO 1 group(p＞0.05).Conclusion:Ischemic postconditioning can provide a protection effect on ischemic reperfusion injury of liver graft after RSLT in rats.The mechanism may associate with activation of endogenous antioxidation system;restrain the production of oxygen free radicals and adhesion of actived neutrophils.The protection effect has a relationship with the on/off "rhythm" of ischemic postconditioning,only a certain on/off persistent time is suitable. Partâ…¢The Impact of Ischemic Postconditioning on Hepatocytes Proliferation of Liver Graft after Reduced-Size Liver Transplantation in Rats with Initial Investigation Of the MechanismsObjective:To investigate the impact of ischemic postconditioning (IPO)on hepatocytes proliferation of liver graft after reduced-size liver transplantation(RSLT)in rats and to study the mechanisms roughly.Methods:Male Spraque-Dawley rats were used as donors and recipients of RSLT and were divided into ischemic reperfusion injury group(IRI group),ischemic postconditioning group(IPO group) according to whether IPO(30sec-30sec on/off,3 cycles)was performed before the liver graft was reperfused sufficiently.The animals were killed at 2h,6h and 24h after reperfusion.Fresh liver tissues were collected to detect the mRNA expression of TNF-α,IL-6,STAT-3 and CyclinD₁.And the expressions of PCNA in donor liver were examined by immunohistochemistry stain methods.Results:After 6h reperfusion,the expression of PCNA began to increase.The PCNA expression in IPO group was stronger than IRI group significantly(p＜0.05)at 6h and 24h after reperfusion,but had no obvious different at 2h after reperfusion(p＞0.05).The mRNA expression of TNF-αin IPO group was lower than IRI group significantly (p＜0.05)at 2h and 6h after reperfusion,but had no obvious different at 24h after reperfusion(p＞0.05).The mRNA expression of IL-6,STAT-3 and CyclinD₁ in IPO group were higher than IRI group significantly(p＜0.05)at 6h and 24h after reperfusion,but all failed to show an obvious different at 2h after reperfusion(p＞0.05).Conclusion:Ischemic postconditioning can promote the hepatocytes proliferation ability of liver graft after RSLT in rats.The mechanism may associate with activation of TNF-α/IL-6/STAT-3 signal transduction way and increase the expression of IL-6 and STAT-3, which are two important facilitative factors for cell proliferation. Ischemic postconditioning can restrain the overexpression of TNF-α, which may help to reduce the ischemic reperfusion injury of liver graft. Partâ…£The Impact of Ischemic Postconditioning on Apoptosis of Liver Graft after Reduced-Size Liver Transplantation in RatsObjective:To investigate the impact of ischemic postconditioning (IPO)on apoptosis of liver graft after reduced-size liver transplantation (RSLT)in rats.Methods:Male Spraque-Dawley rats were used as donors and recipients of RSLT and were divided into ischemic reperfusion injury group(IRI group),ischemic postconditioning group(IPO group) according to whether IPO(30sec-30sec on/off,3 cycles)was performed before the liver graft was reperfused sufficiently.The animals were killed at 2h,6h and 24h after reperfusion.Fresh liver tissues were collected to detect the apoptosis index(AI)with flow cytometry.Results:There were seldom hepatocytes apoptosis in SO group, the AI increase in IPO group and IRI group significantly after reperfusion. The AI in IPO group was lower than IRI group significantly(p＜0.05) at 2h,6h and 24h after reperfusion.Conclusion:Ischemic postconditioning can restraint the hepatocytes apoptosis of liver graft after RSLT in rats,which may help to reduce the ischemic reperfusion injury of liver graft.