ATP诱导大鼠原代培养海马神经元神经毒性及对GAP-43表达的影响

目的:观察不同浓度ATP对大鼠原代培养海马神经元的损伤作用及GAP-43表达的影响,并探讨其可能机制。方法:原代培养新生SD大鼠海马神经元至第8 d,MTT法检测不同浓度ATP作用下海马神经元的存活率,倒置相差显微镜观察海马神经元的形态学改变,免疫荧光细胞化学法观察损伤后海马神经元GAP-43的表达变化,钙离子荧光染料Flou-4/AM检测细胞内钙离子的浓度变化。结果:低浓度ATP对海马神经元无明显影响,高浓度ATP对海马神经元有毒性损伤作用,且呈剂量依赖性。P2X受体拮抗剂可阻断ATP介导的细胞毒性作用,但P2X7受体拮抗剂的阻断作用不明显。高浓度ATP作用海马神经元4 h后,GAP-43的表达水平明显上调,且表达部位发生改变,主要表达于胞体,突起表达减少甚至消失。高浓度ATP组荧光衰减速率明显减慢,说明高浓度ATP参与了海马神经元细胞内钙调节。结论:高浓度ATP对海马神经元有毒性损伤作用,损伤后GAP-43代偿性表达增多,且与细胞内钙离子浓度变化有关,P2X7受体可能不是介导ATP此作用的主要受体亚型。

ATP inuced neurotoxicity and influence on the expression of GAP-43 of the cultured rat hippocampal neurons

Objective: To study the effects of ATP on primary cultured hippocampal neurons and influence on the expression of GAP-43,and the possible mechanism.Methods: The primary hippocampal neurons from neonatal SD rats were cultured in vitro,and MTT assay was used to study the cell survival rate after various concentration ATP treatment at 8 day.The morphological changes in hippocampal neurons were observed under the phase-contrast microscope.Immunofluorescence staining was used to detect the GAP-43 expressional ch...