【摘要】 目的 探讨蛋白激酶C(PKC)和热休克蛋白70(HSP70)在缺血预处理对大鼠肾脏缺血再灌注损伤中的保护作用。方法 将大鼠随机分为对照组(CON)、缺血再灌注组(IR)和缺血预处理后缺血再灌注组(IPC)。除病理组织学变化外,用免疫组化检测各组中不同灌注时间的PKC和HSP70的变化。结果 病理组织学肾小管评分IPC组均低于IR组(P<005),而IPC组和CON组之间无显著性差异(P>005);PKC的表达IPC组明显高于IR组(P<001),并且在再灌注2 h和6 h时,IPC组中的表达明显高于CON组(P<005);HSP70的表达IPC组明显高于IR组(P<001),并且在再灌注2 h和6 h时,在IPC组中的表达明显高于CON组(P<001)。结论 缺血预处理对大鼠肾脏缺血再灌注损伤有保护作用,其保护机制可能与PKC的激活以及与HSP70的诱导合成增多有关。
【关键词】 肾脏;缺血预处理;缺血再灌注损伤;蛋白激酶C;热休克蛋白
【Abstract】 Objective To investigate the role of protein kinase C and HSP70 in the protecitve effect of ischemic preconditioning in rat renal damage of ischemiareperfusion.Methods Rats were randomly divided into control group (CON),ischemiareperfusion group(IP) and ischemic preconditioning group(IPC).In different groups,desides pathological changes,the protein expression of protein kinase C(PKC) and HSP 70 were measured by immunohistochemistry.Results The score of renal tubules in IPC was lower than that in IR (P<005),and the score was similar between IPC and CON (P>005).The protein expression of PKC in IPC was higher than that in IR(P<001),and reperfused for 2 h or 6 h,the expression of HSP70 in IPC was higher than that in IR respectively(P<001),and reperfused for 2 h or 6 h,the expression of HSP70 in IPC was higher than that in CON (P<001).Conclusion Ischemic preconditioning could protect the damage of ischemiareperfusion and the mechanism may be related to the activation of PKC,and may be related to more formation of HSP70.
【Key words】 renal ischemiareperfusion injury,ischemic preconditioning,protein kinase C,heat shock protein
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