缺血后处理对缺血-再灌注肝脏的抗损伤作用研究

目的：探讨缺血后处理（ischemic postconditioning，I-post）对缺血-再灌注（ischemia-reperfusion．I／R）大鼠肝脏的抗损伤作用。方法：建立SD大鼠肝部分I／R损伤模型；实验分为6组：假手术组、单纯缺血组、I／R组、I-post1组、I-post2组和I-post3组；测定血清ALT、AST的活性和肝组织MDA、GSH含量以及SOD、GSH-PX、MPO的活性；观察肝脏病理组织形态学变化和I-post后大鼠的存活率。结果：与I／R组相比，I-post1组和I-post2组大鼠血清ALT和AST活性明显降低（P＜0．05），I-post2组更明显；I-post2组肝组织MDA、MPO显著降低，而SOD、GSH-PX和GSH则明显增加（P＜0．05）；I-post2组大鼠存活率高于I／R组。结论：缺血后处理对缺血-再灌注大鼠肝脏有明显的抗损伤作用，其可能与降低活性氧的产生、保护肝脏抗氧化系统和减轻中性粒细胞聚集程度有关。

The Protective Role of Ischemic Postconditioning Against Ischemia- reperfusion Injury in Rat Liver

Objective: To study the protective role of ischemic postconditioning(I-post) against ischemia-reperfusion(I/R) injury in rat liver.Methods: Using rat model of hepatic segmental I/R injury,rats were divided into 6 groups which were sham operation group(S),ischemia group(I),I/R group(I/R),I-post 1,I-post 2 and I-post 3 respectively.Serum alanine aminotransferase(ALT) and aspartate aminotransferase(AST),and malondialdehyde(MDA),gultathionine(GSH),superoxidase dismutase(SOD),gultathionine peroxidase(GSH-Px) and myeloperoxidase(MPO) in hepatic tissue were measured respectively.In addition,survival rates of I/R and I-post 2 groups were evaluated.Results: Compared with I/R group,I-post 1 and I-post 2 groups had a significant decrease in ALT and AST release and tissue injury.In I-post 2 group,the values of MDA and MPO were lower and activities of SOD,GSH-PX and GSH were higher than those of I/R group(P<0.05).With respect to the survival rate I-post 2 was higher than I/R group.Conclusions: I-post can result in protection against hepatic I/R injury,which is related to reducing the production of reactive oxygen species,maintaining the activities of antioxidant systems and suppressing neutrophils recruitment.