大鼠局灶性脑缺血再灌注后Ref-1、NF-κB及IκB的表达

Expressions of Ref-1,NF-κB and IκB after transient focal cerebral ischemia-reperfusion in rats

目的研究大鼠局灶性脑缺血再灌注损伤后Ref-1蛋白、NF-κB及IκB的动态变化。方法采用大脑中动脉线栓法制作局灶性脑缺血再灌注模型,应用免疫组化法检测Ref-1、NF-κB、IκB的动态表达。结果与对照组及假手术组相比,脑缺血再灌注后,随着再灌注时间的延长,Ref-1蛋白、IκB阳性细胞数逐渐减少(P<0.05),NF-κB蛋白阳性细胞数逐渐增加(P<0.05)。结论脑缺血区再灌注损伤可导致Ref-1蛋白酶活性下降、IκB降解,引起NF-κB的激活,进一步导致自由基大量产生,加重了细胞内DNA的损伤,从而促进损伤区的神经元凋亡。

Objective To investigate the dynamic changes of Ref-1, NF-κB, IκB in focal cerebral ischemia and reperfusion. Methods Middle cerebral artery occlusion （MCAO） in rats was used to establish focal cerebral ischemia-reperfusion model. The dynamic expressions of Ref-1, NF-κB and IκB were observed by immunohistochemistry. Results Compared with the control group and the sham-operation group, Ref-I positive cells and IκB positive cells decreased gradually （P〈0.05） following prolonged cerebral reperfusion, while NF-κB positive cells increased gradually （P〈0.05）. Conclusion Cerebral ischemia-reperfusion injury leads to the decrease of Ref-I protein enzyme activity, the degradation of IκB, and the activation of NF-κB, and thereby the production of free radicals, exacerbation of DNA damage and aggravation of apoptosis of neurons.