黄芪对大鼠脑缺血再灌注损伤c-fos和Bcl-2表达及细胞凋亡的影响

目的探讨黄芪对脑缺血再灌注损伤大鼠神经细胞凋亡和凋亡基因c-fos、Bcl-2表达的影响。方法 40只Wistar大鼠,体质量180～220 g,随机分为黄芪组、缺血4 h再灌注1 h组(Ⅰ组)、缺血4 h再灌注12 h组(Ⅱ组)、缺血4 h再灌注24 h组(Ⅲ组)和对照组。线栓法建立脑缺血再灌注损伤大鼠模型。切片分别行HE染色,应用免疫组织化学染色检测神经细胞凋亡基因c-fos、Bcl-2蛋白表达。结果对照组、Ⅰ组脑细胞未见明显变化,Ⅱ组轻度脑细胞水肿,Ⅲ组脑细胞明显水肿,黄芪组损伤区范围变小,肿胀减轻。与对照组比较,其余各组脑细胞c-fos和Bcl-2阳性表达率增高(P<0.01);黄芪组c-fos和Bcl-2阳性表达率较Ⅱ、Ⅲ组降低(P<0.01)。Ⅰ、Ⅱ、Ⅲ组和黄芪组细胞凋亡指数较对照组明显增加(P<0.01);黄芪组较Ⅱ、Ⅲ组明显降低(P<0.01)。结论黄芪在脑缺血再灌注损伤后可抑制c-fos表达、增加Bcl-2表达,减轻脑细胞凋亡。

Effects of astragalus on apoptosis and c-fos,Bcl-2 expression after focal ischemia-reperfusion injury in rats

Objective To explore the effects of astragalus on apoptosis and c-fos,Bcl-2 expression after focal cerebral ischemia-reperfusion injury in rats.Methods Forty male Wistar rats（180-220 g） were randomly divided into astragalus group,4 hours ischemia/1 hour reperfusion group（group I）,4 hours ischemia/12 hours reperfusion group（groupⅡ）,4 hours ischemia/24 hours reperfusion group（group Ⅲ） and control group.The model of cerebral ischemia-reperfusion in rats were made by a suture-occluded method.The microtome section were given hematoxylin eosin（HE） staining.The expressions of c-fos and Bcl-2 were detected by immunohistochemistry staining.Results HE staining showed that the control group and group I was no significant change in brain cells,and mild edema of brain cells appeared in group Ⅱ,obviously edema appeared in group Ⅲ.The damage area of astragalus group was smaller and edema reduced.Compared with the control group,the positive expression rates of c-fos and Bcl-2 of other four groups were increased（P0.01）;the positive expression rates of c-fos and Bcl-2 of astragalus group were lower than those in group Ⅱand group Ⅲ（P0.01）.The apoptotic index of group I,groupⅡ,groupⅢ and astragalus group was significantly higher than that of the control group（P0.01）;the apoptotic index of astragalus group was significantly lower than that of group Ⅱand group Ⅲ（P0.01）.Conclusion Astragalus can inhibit the expression of c-fos and increase the expression of Bcl-2 in cerebral ischemia reperfusion and lessen brain cell apoptosis.