缺血性急性肾衰大鼠肾组织细胞周期调节蛋白表达的变化

The expression of cell cycle regulating proteins-cyclin E and cyclin dependent kinase 2 in rats with ischemic acute renal failure

目的 :探讨缺血性急性肾功能衰竭大鼠肾组织细胞周期调节蛋白cyclinE和CDK 2的表达及与肾小管上皮细胞增生的关系。 方法 :建立缺血性急性肾功能衰竭大鼠模型 ,分别在第 0、2、7、10、14天处死。以生化法测定血清肌酐 (SCr)值 ,以免疫组织化学染色技术观察肾组织内细胞增生程度以及cyclinE和CDK 2的表达和分布情况。 结果 :大鼠SCr值在缺血再灌注第 2天开始显著增高 ,第 7天最高 ,第 10天开始降低 ,第 14天基本降至正常。对照组肾组织细胞增生指数 (PI)为 0 1% ,肾缺血后第 2、7、10和 14天PI分别为 14 8%、30 9%、2 3 6 %和12 4%。cyclinE和CDK 2蛋白在肾组织内分布于皮质肾小管 ,少数在间质 ,且肾缺血后第 2天表达弱阳性 (+) ,第7天表达强阳性 (+++) ,第 10天表达阳性 (++) ,第 14天表达弱阳性 (+) ;肾小球内基本无表达。 结论 :缺血性急性肾功能衰竭大鼠肾组织cyclinE/CDK 2蛋白表达增强与肾小管上皮细胞增生程度相一致。表明cyclinE和CDK 2是调控缺血性急性肾衰大鼠肾小管上皮细胞增生的关键蛋白。

Objective:To investigate the expression of cell cycle regulating proteins-cyclin E and cyclin dependent kinase 2(CDK 2) in renal tissue of rats with ischemic acute renal failure and its relationship with the regeneration of tubular epithelial cells. Methodology:The rat models with acute renal failure by induced ischemia and reperfusion of kidney were established.These rats were sacrified on 0,2,7,10 and 14 days,respectively.The blood samples were obtained for the measurement of serum creatinine by routine method.The samples of renal cortex were obtained for the observation of renal cellular proliferation,and detection of cyclin E and CDK 2 expression by using immunohistological and protein immunoblotting method. Results:The level of serum creatinine increased slightly on day 2 and reached the highest level at day 7.Then,it was decreasing from day 10 and returned grodually to normal level at day 14.The proliferating index(PI)or rate reflecting the degree of cell proliferation measured was 0 1%,14 8%,30 9%,23 6%,and 12 4% on day 0,2,7,10,and 14 respectively.Cell cycle regulating proteins-cyclin E and CDK 2 were obtained mainly in renal tubullar cells,lower amount in the interstitium,while not in glomeruli being tested.The changes of cyclin E and CDK 2 expression in renal tissue were similar to the changes of proliferating rate after the acute renal failure happening.On day 2,the expression of cyclin E and CDK 2 showed slightly positive,demonstrating on day 7 and day 10 strongly positive,then on day 14 remained trace. Conclusion:The regeneration of renal tubular epithelial cells after acute ischemic renal injury was closely related with the expression of cyclin E and CDK 2 in renal tissue of the rats in our study.