Bax、Bcl-2在培养新生鼠皮层神经元中的表达及L-NAME的干预作用

目的　探讨Bax与Bcl-2在体外培养的皮层神经元的表达及非选择性一氧化氮合酶抑制剂NG-硝基-L-精氨酸甲酯（L-NAME）的干预作用。 方法　原代培养SD新生大鼠皮层神经元，并采用neuron specific enolase (NSE)免疫荧光方法进行细胞纯度鉴定。神经元随机分为正常组、N-甲基-D-天门冬氨酸（NMDA）组、NG-Nitro-L-arginine Methyl Ester（L-NAME）组，分别采用ELISA检测各组细胞中一氧化氮合酶（nitric oxide synthase, NOS）的表达，采用RT-PCR、Western blot分别检测各组细胞中Bax、Bcl-2 mRNA及蛋白的表达。 结果　NSE免疫荧光大多数细胞为NSE阳性细胞，神经元纯度高达90%；L-NAME组中NOS及Bax的表达均高于正常组而低于NMDA组， Bcl-2的表达低于正常组而高于NMDA组。 结论　L-NAME对NMDA诱导的神经细胞凋亡起明显的保护作用，其可能是通过上调Bcl-2的表达、下调Bax的表达发挥作用。

The expression of Bax and Bcl-2 in cultured neonatal rat cortical neurons and the role of L-NAME intervention

Objective　To investigate the expression of Bcl-2 and Bax in cultured cortical neurons after NMDA injury and intervention effect of L-NAME.　Methods 　The primary cortical neurons were identified by polyclonal antibody against NSE. The neurons were randomly divided into 3 groups: control group, NMDA-injured group, L-NAME pretreatment group. ELISA was employed to explore the expression of NOS, and the expression of Bcl-2 and Bax was detected by RT-PCR and Western blot. 　Results 　Immunofluorescence test showed that the most cells were NSE positive staining cells. NOS in L-NAME group were higher than that in control group, but lower than that in NMDA group; the expression of Bcl-2 mRNA and protein in L-NAME group were lower than in control group, but higher than that in NMDA group. The expression of Bax was in contrast with Bcl-2.　Conclusion　L-NAME plays an important protective role in neuronal apoptosis induced by NMDA, the possible mechanism of which may be related with up-regulation of Bcl-2 expression and down-regulation of Bax expression.