促红细胞生成素对大鼠脑缺血再灌注神经元凋亡、bcl-2和bax表达的影响

目的观察促红细胞生成素(Epo)对大鼠局灶性脑缺血再灌注神经细胞凋亡及凋亡相关蛋白bc l-2、bax表达的影响。方法60只SD大鼠随机分为6组,缺血再灌注治疗A组、B组、C组、D组(分别在缺血前30 m in及再灌注后2 h、6 h、12 h腹腔注射Epo 3 000 IU.kg-1)、缺血再灌注组(E组)和假手术组(F组)。观察Epo对大鼠脑缺血再灌注后脑组织的病理变化,Epo、bc l-2、bax的表达及神经细胞凋亡情况。结果(1)A组、B组、C组及F均未见明显病理性改变,D组及E组显示梗死区神经元缺血改变;(2)各组均可见不同程度Epo阳性表达细胞,且A组、B组、C组较D组、E组表达明显增多(P<0.05);(3)TUNEL法见A组、B组、C组、F组凋亡阳性细胞较D组、E组明显减少(P<0.05);(4)A组、B组、C组bc l-2蛋白表达较D组、E组、F组明显增多(P<0.05),而bax蛋白表达较D组、E组及F组明显减少(P<0.05)。结论Epo通过调控凋亡相关基因bc l-2/bax的比率而发挥抗神经元凋亡的脑保护作用。

Effects of erythropoietin on neural apoptosis and expression of bcl-2 and bax in rats induced by cerebral ischemia-reperfusion

Objective To observe the effects of erythropoietin(Epo) on neural apoptosis,expression of bcl-2 and bax in rats induced by focal cerebral ischemia-reperfusion.Methods Sixty Sprague-Dawley rats were randomly divided into six Epo-treated groups A,B,C,D,which were performed with intraperitoneal injection of 3 000 IU·kg~(-1) Epo 30 min before ischemia and 2 hours,6 hours and 12 hours after reperfusion.non-treated group(E) and sham-operation(F).HE staining,immunohistochemistry,and TUNEL were used to observe pathological changes and the expression of Epo,bcl-2,bax and neural apoptosis.Results 1.No obvious pathological changes demonstrated in group A,B and C and F,ischemic changes of neuron in infarction zone in group D and E.2.The expression of Epo were greatly increased in group A,B and C than in that of group D and E(P<0.05).3.Positive apoptosis cells in group A,B and C and F were decreased remarkably than that in group D and E(P<0.05).4.The expression of bcl-2 in group A,B and C were significantly increased than that of group D,E and F(P<0.05) and the expression of bax in group A,B and C were greatly decreased than that of group D,E and F(P<0.05).Conclusion Epo serves neuroprotective effects and anti-apoptosis by regulating ratio of apoptosis related gene bcl-2/bax.