不同缺血预处理方案对大鼠肾脏缺血再灌注损伤组织HSP70表达的研究

Expression of HSP70 on renal ischemia injury in rat models by different ischemic preconditioning

目的探讨单、多循环两种缺血预处理方案对大鼠肾脏急性缺血再灌注损伤的保护作用及对HSP70表达的影响。方法60只雄性SD大鼠切除右肾、分离出左肾动脉后随机均分为四组。1)缺血再灌注(I/R)组;2)单循环缺血预处理(SCP)组;3)多循环缺血预处理(MCP)组;4)假手术(Sham)组。24 h取材行生化、常规病理、免疫组化检查及肾小管损伤评分。结果假手术组未见明显改变;肌酐(Scr)水平、肾小管损伤评分单循环缺血预处理组多循环缺血预处理组低于缺血再灌注组,差异显著;多循环缺血预处理组低于单循环缺血预处理组,差异显著(P<0.01)。HSP70表达水平多循环缺血预处理组最高。结论缺血预处理可从功能和组织学上减轻肾脏的急性缺血再灌注损伤,多循环预处理方案诱导HSP70表达及保护作用在24 h内强于单循环的方案。

Objective To evaluate renal protection and the expression of HSP70 between schedules of single--cycle and multi-cycles ischemie precondition （IP） in rats. Methods 60 male Sprague-- Dawley rats were divided randomly into 4 groups after right kidney nephreetomy： Group 1 was for ische- mia--reperfusion （I/R）, Group 2 was for single--cycle ischemic precondition （SCP）, Group 3 was for multi--cycles ischemic precondition （MCP）, Group 4 was sham--operated controls. HSP70 expression in kidney tissues was determined by immunohistochemical method. The grading scale of tubular ischemic injury and the serum creatinine also examined after 24 hour. Results Serum creatinine （ser） level in all groups increased markedly, compared to sham group （ P〈0. 01） . Scr concentration, tubular ischemic injury index and the expression of HSP70 changed significantly after IP in SCP and MCP groups, com- pared to I/R group. Furthermore, they were showed in a more obviously level in MCP group, compared to that in SCP group. Conclusions Isehemic preconditioning can protect kidney from ischemia injury on histological and biochemical level. The renal ischemic preconditioning which induced by 2 minutes occlusion, 5 minutes reperfusion and repeated for 3 cycles, followed by 45 minutes re--ischemia showed better protection and higher expression of HSP70 than the single--cycle ischemic precondition.