流式细胞术检测局灶性脑缺血再灌注bcl-xl、bax蛋白表达

目的 探讨应用流式细胞术检测bcl-xl和bax在局灶性脑缺血再灌注中的表达及作用。方法 45只健康雄性Wistar大鼠随机分为正常对照组、假手术组。缺血3 h组和缺血3 h再灌注组;缺血再灌注组又分为缺血再灌注3h、6h、12h、24h、48h和72h等6个亚组。采用线栓法复制大脑中动脉脑缺血再灌注模型,应用流式细胞术检测bcl-xl和bax蛋白表达。结果 缺血3 h再灌注各亚组,随再灌注时间的延长,半影区bax表达逐渐增强,于再灌注24 h和48 h达高峰(均P<0.01);bcl-xl表达在早期增强后随即呈下降趋势,bcl-xl/bax比值呈动态变化。再灌注中心区,在缺血再灌注早期bcl-xl和bax表达均增强(P<0.05或P<0.01),随着再灌注时间的延长,二者的表达及bcl-xl/bax比值逐渐减弱。结论 bcl-xl表达增强有利于促进神经细胞存活,而bcl-xl与bax比值的转变则促进神经细胞凋亡。

Expression of bcl-xl and bax proteins during reperfusion after focal cerebral ischemia

Objective The expressions and actions of bcl-xl and bax proteins during reperfusion after focal cerebral ischemia were studied. Methods Forty-five healthy male Wistar rats were randomly divided into control group, pseudo-operative group, ischemia for 3 hr group and reperfusion after ischemia for 3 hr group. The reperfusion after ischemia group was further divided randomly into 6 sub-groups reperfusion at 3, 6, 12, 24, 48 and 72 hr after ischemia. The expressions of bcl-xl and bax proteins were examined in a focal cerebral ischemic model by flow cytometry(FCM). Results The expression of bax increased gradually during the reperfusion with the prolongation of ischemic time about 3 hr. It reached its peak from 24 h to 48 h of reperfusion, while the expression of bcl-xl increased at the early stage but then reduced. The ratio of bcl-xl/ bax showed dynamic changes. Conclusion The increase of bcl-xl expression promotes the nerve cell survival. The changes of bcl-xl/bax ratio promote the apotosis of nerve cell.