【摘要】 目的:本研究通过观察体外培养的大鼠胚胎海马神经元在谷氨酸损伤后,细胞活力变化及细胞损伤的方式,初步探讨谷氨酸对神经元的损伤机制。方法:通过MTT,观察不同浓度(62.5μM、125μM、250μM、500μM)的谷氨酸损伤后不同时间(6 h、12 h、18 h、24 h)海马神经元活力的变化。经相差显微镜观察谷氨酸对海马神经元胞体及突起的影响。通过TUNEL、Hoechst染色比较正常培养组和损伤组的凋亡率,分析谷氨酸对海马神经元的损伤作用。结果:MTT结果显示,谷氨酸对体外培养的胎鼠海马神经元有兴奋毒性,在所观察的剂量范围内,随着谷氨酸浓度的增加,作用逐步增强,至500μM达峰值,随着损伤后孵育时间的延长,海马神经元活力逐渐下降。TUNEL和Hoechst染色结果也显示,125μM谷氨酸对体外培养的胎鼠海马神经元有兴奋毒性,主要引起海马神经元的凋亡。结论:谷氨酸对体外培养的胎鼠海马神经元有兴奋毒性,且这种作用呈现剂量相关性。中等剂量(125μM)谷氨酸损伤主要引起海马神经元的凋亡。更多还原

【Abstract】 Objective:To investigate the changes of cell vitality in cultured hippocampal neurons after glutamate stimulation, and the cellular mechanisms involved in neurotoxicity.Methods:Different concentrations of glutamate (62.5μM,125μM,250μM,500μM) were applied to the cultured rat embryonic hippocampal neurons.Methyl-thiazole-tetrazolium (MTT) assay was used to detect the neuronal vitality after incubation different periods (6 h,12 h,18 h,24 h).After glutamate was applied to the cells,phase contrast microscope,TUNEL and Hoechst assay were used to identify the glutamate-induced neurotoxicity. Results:The results of MTT indicated that glutamate could evoke neurotoxieity to the cultured hippocampal neurons,and when the concentrations of glutamate and the incubation time increased,the neurotoxicity augmented.Morphological observa- tion,TUNEL and Hoechst revealed that glutamate induced hippocampal cell death in a prevailing form of apeptosis.Conclu- sion:Glutamate have obviously neurotoxicity in cultured 7～8 days hippocompal neurons in a dose-effect character,with apoptosis predominating after exposure to medium concentrations of glutamate in a delayed time course.更多还原