β-淀粉样肽（25-35）对PC12细胞bax和bcl-2基因表达的影响

目的：观察β-淀粉样肽25-35（β-amyloid peptide 25-35,Aβ25-35）诱导PC12细胞凋亡和对bax及bcl-2基因表达的影响。方法：采用MTT法检测PC12细胞的存活率;DNA电泳法观察细胞凋亡时特异性梯状条带;Hochest33258-PI荧光染色观察细胞核形态学改变;RT-PCR检测bax和bcl-2基因mRNA表达变化,Western blot检测Bax和Bcl-2蛋白表达变化。结果：随着Aβ25-35浓度的增加,PC12细胞存活率逐渐降低;DNA电泳呈凋亡特异性梯状条带;荧光染色可见细胞核碎裂、核固缩等凋亡特征;bax mRNA及Bax蛋白表达增加,bcl-2 mRNA及Bcl-2蛋白表达降低。结论：在Aβ25-35诱导PC12细胞凋亡过程中,Bax和Bcl-2可能起重要作用。

Effect of β-amyloid Peptide 25-35on Expression of Genes bax and bcl-2 in PC12 Cell

Objective：To observe the apoptosis induced by β-amyloid peptide 25-35（Aβ25-35） and the effect of Aβ25-35 on expression of genes bax and bcl-2 in cultured PC12 cells.Methods：Cell survival rate of PC12 cells with MTT assay,apoptosis of PC12 cells with DNA electrophoresis and Hochest 33258-PI fluorescence staining,and the expression of bax and bcl-2 mRNA and level of Bax and Bcl-2 protein with RT-PCR and Western blot were evaluated respectively.Results：The survival rate of PC12 cells was showed decreased by Aβ25-35in a dose-dependent manner.DNA electrophoresis and Hochest33258-PI fluorescence staining showed apoptosis during the drug treatment.The bax mRNA and protein levels were increased,and the bcl-2 mRNA and protein levels were decreased.Conclusion：Bax and Bcl-2 proteins may play an important role in the process of PC12 cells apoptosis induced by Aβ25-35.