银杏内酯B对背根神经节神经元谷氨酸损伤的保护作用

Neuroprotective Effect of Ginkgolides on Cultured Dorsal Root Ganglion Neurons with Neurotoxicity Induced by Glutamate

目的:观察银杏内酯B(Gin)对体外培养的胚胎大鼠背根神经节(DRG)神经元谷氨酸(Glu)损伤的保护作用。方法:Wistar胎鼠DRG神经元分散培养48h后,用Glu(200μmol/L)造成神经元损伤(Glu损伤组),并同时给予Gin50μmol/L(Gin保护组),观察添加Gin和未添加Gin孵育的Glu损伤的神经元活细胞生长状况,并且利用流式细胞仪检测各组神经元的凋亡率,共聚焦激光扫描显微镜(CLSM)检测各组细胞内钙离子荧光强度。结果:用Gin孵育的DRG神经元生长状况良好,接近于正常对照组细胞,较损伤组DRG神经元生长状态有明显改善;Glu损伤组DRG神经元细胞凋亡率(41.1%)高于对照组(2.5%)和Gin保护组(7.6%)。Glu损伤组细胞内钙离子荧光强度较对照组明显增高(P<0.01),Gin保护组细胞内钙离子荧光强度较Glu损伤组明显降低(P<0.01),Gin保护组DRG神经元胞体内钙离子的荧光强度与正常对照组相比差异无统计学意义(P>0.05)。结论:Gin可通过减低钙离子内流,从而对Glu损伤的DRG神经元产生保护作用。

Objective：To determine the neuroprotective effect of ginkgolides （Gin）on cultured rat embryos dorsal root ganglion（DRG） neurons injured by glutamate （Glu） in vitro.Methods：DRG neurons of Wistar rat embryos were cultured in vitro for 48 h and then exposed to Glu （200 μmol/L） with or without Gin （50 μmol/L）.The living cells were observed with an inverted contrast microscope.The cultures were processed for detecting the apoptosis rate by using flow cytometry.The fluorescent intensity of intracellular Ca2＋ was detected by confocal laser scanning microscope （CLSM）.Results：The living status of DRG cells with Gin incubation was better than that of incubated cultures without Gin.The shape of neuronal cell bodies or neurite networks were almost the same in the glutamic acid group with Gin compared with that of the normal control group.The apoptosis rate of cells incubated with Glu for 24 h was 41.1% in DRG cultures.The apoptosis rate of cells incubated with Glu and 50 μmol/L of Gin for 24 h was 7.6% in DRG cultures.The fluorescent intensity was lower in Gin with Glu group than that in Glu group （P〈0.01）.The fluorescent intensity was lower in the control group than that in Glu group（P〈0.01）.There was no significant difference in the fluorescent intensity between Gin with Glu group and control group （P〉0.05）.Conclusion：Ginkgolides may reduce intracellular Ca^2＋ concentration,and then protect DRG neurons from neurotoxicity induced by Glu.