氯沙坦对大鼠肾脏缺血/再灌注损伤中STAT-1及ICAM-1蛋白表达的影响

目的：研究氯沙坦在肾缺血/再灌注损伤中对STAT-1和ICAM-1蛋白表达的影响及在损伤修复过程中的作用。方法：大鼠背部双侧切开找到肾蒂,行无创动脉夹夹闭造成急性肾缺血/再灌注损伤模型,以氯沙坦预处理灌胃,苦味酸法测血清肌酐,免疫组化测肾组织切片中的STAT-1蛋白和ICAM-1蛋白表达的水平。结果：假手术组在6h和24h肾组织的病理和血肌酐数值无明显变化;模型组在缺血再灌注6h和24h与假手术组对比血清肌酐数值明显升高,肾组织切片在6h时STAT-1和ICAM-1蛋白已有表达,24h时两指标表达均明显上调;氯沙坦预处理组在缺血再灌注损伤6h和24h时与模型组对比,血肌酐数值明显下降,同时肾组织中STAT-1和ICAM-1蛋白表达也明显下调。结论：氯沙坦在肾缺血再灌注损伤中起保护作用,机制可能通过下调STAT-1和ICAM-1蛋白表达有关。

Effects of Astragalus on the Expressions of STAT-1 and ICAM-1 Kindey in Rat After Ischemia/Reperfusion Injury

Objective:To investigate the possible effect of Losartan on the expressions of STAT-1 and ICAM-1 in rats with renal ischemic-reperfusion injury(IRI),in order to explore its effects in rats with renal IRI.Methods:Thirty-six healthy male wistar rats were randomly divided into three groups:sham groups,model groups,Losartan treatment group(n=12).Within each group,rats were randomly divided into two subgroups:IR6h and IR24 h groups(each subgroup n=6).The renal models of acute ischemia-reperfusion were made in rats by placing the vascular clamp in bilateral renal pedicle to block the blood circulation for 45 minutes.In sham group,renal arteries were founded but not clipped for 45 minutes.The Losartan treatment group were treated by injecting into stomach with Losartan potassium(80 mg·kg-1·d-1) for 7 days before ischemia respectively.The sham and model groups were received the same volume of the distilled water for 7 days before surgery.The level of blood serum creatinine(Scr) was measured 6 h and 24 h after reperfusion,then the rats were euthanized in batch.Histopathological damages were monitored accordingly.The expressions of STAT-1 and ICAM-1 in renal tissue were measured by immunohisto-chemical stain.Results:In sham group,the renal pathological are normal and the level of Scr did not change clearly.In model group,the level of Scr was markedly higher than that of the sham group 6 h and 24 h after reperfusion respectively(both P<0.05)Further,the protein expressions of STAT-1 and ICAM-1 in renal tissue were detected 6 h after reperfusion,and to peak 24 h later.Compared with model group,the level of Scr was lower 6 h and 24 h after reperfusion in Losartan group.As well,the expression of STAT-1 and ICAM-1 were markedly lower than model group at the same time point after reperfusion(P<0.01).Conclusion:The pretreatment of Losartan can protect renal function against the renal ischemia-reperfusion injury.As the levels of blood serum creatinine decreased,the expression level of STAT-1 and ICAM-1 protein were markedly downregulated after the ischemia-reperfusion injury.These results imply that Losartan whose mechanism may be involved in the inhibition of STAT-1 expression can protect renal against the acute renal ischemia/reperfusion injury.