HSP70在大鼠肝移植缺血预处理中的变化及其保护效应

目的:研究热休克蛋白70(heat shock protein,HSP70)在大鼠肝移植供肝缺血预处理中的变化及其产生的保护效应.方法:建立大鼠原位肝移植缺血预处理模型.随机分成3组:未行肝移植对照组(C组)、肝移植(liver transplantation,LT)组和缺血预处理肝移植(ischemic precondition,IP)组.术后在分析各组供肝组织HSP70表达变化的同时,检测血清丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)活性,供肝组织超氧化物歧化酶(SOD)、ATP含量,并在光镜下观察各组肝细胞形态学改变.结果:与C组相比,LT组HSP70表达量轻度增高,而IP组显著升高(P＜0.05).LT组血清ALT、AST活性显著高于C组,肝组织SOD、ATP含量呈相反变化(P＜0.05);与LT组相比,IP组血清ALT、AST活性明显降低,肝组织SOD、ATP含量显著升高(P＜0.05).光镜下观察到LT组供肝细胞形态学出现明显损伤性改变,而IP组改变较小.结论:缺血预处理可以诱导大鼠原位移植肝高表达HSP70,后者可能是减轻缺血再灌注对供肝损伤的一个重要保护分子.

Ischemic preconditioning increases HSP70 expression and its protective effects in rats orthotopic liver transplantation

Objective: To determine the changes of HSP70 expression and its protective effects in rats orthotopic liver transplantation. Methods: Being used as donors and recipients of orthotopic liver transplantation, rats were divided randomly into non-liver-transplantation troup (Group C), liver transplantation group (Group LT) and ischemic preconditioning plus liver transplantation group(Group IP). After operations ,HSP70 expression and the contents of SOD and ATP of liver tissue were determined, the changes of cellular morphology of liver tissue were observed by optical microscope,and the serum AST and ALT levels were assayed simultaneously. Results:Compared with Group C.HSP70 increased slightly in Group LT and significantly in Group IP(P<0. 05). The levels of ALT and AST in Group LT were considerably higher than those of Group C; the changes of SOD and ATP levels were the reverse(P<0. 05). Compared with Group LT,the ALT and AST levels in group IP dropped considerably while the SOD and ATP levels increased significantly(P<0. 05). The liver cells were obviously injured in Group LT and their changes were slight however,in Group IP. Conclusion: Ischemic preconditioning can induce the overex-pression of HSP70 after orthotopic liver transplantation in rats. HSP70 may be an important protecting factor in relieving ischemic reperfusion injury to the donated liver.