铝致大鼠海马神经细胞凋亡及对Bcl-2和Bax表达的影响

[目的]探讨铝对大鼠海马神经细胞凋亡及Bcl-2、Bax表达的影响。[方法]健康雄性SD大鼠40只,按体重随机分为4组:生理盐水组(对照组)、Al3+2.5mg/kg组、Al3+5mg/kg组、Al3+10mg/kg组。AlCl3溶液腹腔注射染毒,60d后处死,用TUNEL法检测细胞凋亡,免疫组化法测Bcl-2、Bax的表达,并用图像分析系统进行结果分析。[结果]随着染铝剂量的增高,大鼠海马神经细胞凋亡指数升高,存在剂量-效应关系(P<0.05)。各染铝组Bcl-2表达下降,Bax表达显著升高,Bcl-2/Bax逐渐下降,存在剂量-效应关系(P<0.05);海马神经细胞凋亡指数与Bcl-2呈负相关(r=一0.924,P<0.01),与Bax呈正相关(r=0.804,P<0.01),与Bcl-2/Bax表达比值呈负相关(r=-0.872,P<0.01)。[结论]铝可以诱导大鼠海马神经细胞凋亡,其机制可能与Bcl-2表达下调,Bax表达上调以及Bcl-2/Bax表达比值下降有关。

The Effect of Aluminum on the Apoptosis of Hippocampus Cells and the Expression of the Bcl-2 and Bax in Rats

[Objective] To explore the effects of aluminum chloride( AlCl3) on the apoptosis of rat hippocampus cells and the relationship between the apoptosis and the expression of the Bcl-2 as well as Bax. [ Methods] 40 SD rats, adult and healthy, were divided into 4 groups at random:normal saline,2.5 mg/Al3+ kg,5 mg Al3+/kg, 10 mg Al3 + /kg.The rats were given AlCl3 by intraperitoneal injection, for 60days. After treatment, the apoptosis of hippocampus cells was measured by method of TUNEL.The expression of Bcl-2 and Bax in rats' hippocampus was measured by immuno-histochemical method.The results were analyzed by the imaging analyzing system. [Results] The apoptosis index(AI) of hippocampus cells become higher with the increasing of the dose of aluminum. and there is a dose-effect relationship between them.The expression of Bcl-2 significantly decreased,The expression of Bax significantly increased in hippocampus cells and the value of Bcl-2 /Bax decreased significantly, with the increasing of the dose of aluminum and there is a dose-effect relationship between them(P<0.05) . AI negatively correlated with the expression of Bcl-2( r=-0.924, P<0.01) and the value of Bcl-2/Bax(r = 0.872,P<0.01);There was positive correlation between AI and the expression of Bax(r=0.804,P<0.01) . [Conclusion] Aluminum may induce apoptosis in rat hippocampus cells through the down-regulation of Bcl-2 ,the up-regulation of Bax expression, and the decrease of Bcl-2 /Bax.