TLR4和NF-κB在大鼠肾缺血再灌注损伤中的表达及意义

Expression and Significance of TLR-4 and NF-κB in Rats with Kidney Ischemia Reperfusion Injury

目的:观察大鼠肾缺血再灌注损伤后Toll样受体4(TLR4)和核因子-κB(NF-κB)的表达变化及其关系。方法:将40只SD大鼠随机等分为假手术组(S组)和肾缺血再灌注损伤组(I/R组),建立肾缺血再灌注模型。在肾缺血再灌注后24 h切取肾脏。采用免疫组织化学法观察TLR4蛋白及NF-κB蛋白在肾脏组织中的表达变化及其相关性;采用半定量逆转录聚合酶链反应(RT-PCR)检测两组肾组织中TLR4、NF-κB的mRNA水平表达变化。结果:TLR4蛋白在S组大鼠肾小管细胞中有少量表达,在I/R组24 h后肾组织中表达明显增加,与S组比较,差异有统计学意义(P<0.05)。NF-κB P65蛋白在S组大鼠肾小管细胞胞浆和少量胞核中有表达。在I/R组24 h后肾小管细胞胞浆和胞核均可见NF-κB P65明显表达,差异有统计学意义(P<0.01)。TLR4和NF-κB在肾缺血再灌注损伤组织中的表达具有明显的相关性。I/R组中的TLR4 mRNA、NF-κB mRNA表达均较S组上调,差异有统计学意义(P<0.05)。结论:大鼠肾缺血再灌注损伤后,肾组织TLR4和NF-κB P65的表达明显上调,且有明显的相关性。TLR4有可能通过激活NF-κB继而引起下游的炎症因子募集,介导肾缺血再灌注损伤。

Objective：To explore the relationships between the expression of TLR4 and NF-kB in rats with kidney ischemia reperfusion injury and its significance. Methods;40 male SD rats were randomly divided into sham operation group （S, n= 20）, ischemia reperfusion 24 h group （I/R, n= 20）. The expression and distribution of TLR4 and NF-kB in kidney isehemic reperfusion were determined by immunohistochemistry. Reverse transcrip- tional-polymerase chain reaction （RT-PCR） was performed to evaluate the mRNA levels of TLR4 and NF-kB. Results ： Compared with the sham group,the expression of TLR4 in renal tubular epithelial cell（TEC） of kidney and the expression of NFlcB in cytoplasm and nucleus significantly increased in ischemia reperfusion 24 h group. （P〈 0. 05 and P〈0. 01, respectively）. TLR4 and NF-kB mRNA expressions were up-regulated in I/R group compared with the sham one. （P〈0. 05 and P〈0. 05, respectively）. Conclusions：The expression of TLR4 and NF-gB may mediate the inflammatory injury in the process of kidney ischemis reperfusion and inhibitors to TLR4 may be benefit for attenuating the kidney injury induced by ischemia reperfusion and subsequent acute inflammatory response.