乙酰胆碱对神经细胞膜结构影响

Structural observation of membrane surface of acetylcholine -treated neurons

目的探讨乙酰胆碱(ACh)对神经细胞超微结构和存活率的影响。方法不同浓度 ACh作用于原代培养大鼠海马神经元,原子力显微镜观察细胞超微结构的变化,四甲基偶氮唑盐 (MTT)微量酶反应比色法测定MTT代谢率。结果正常海马神经元表面光滑,ACh作用后神经元发育迟缓,胞膜表面粗糙,出现隆起和孔洞样结构,直径为100 nm-1μm,深度为100～400 nm,损伤程度有时间依赖性和剂量依赖性;ACh可使MTT代谢率明显降低(P<0．05),具有剂量依赖性。结论一定浓度的ACh可损伤神经细胞膜,进一步降低细胞存活率。

Objective To investigate the effects ofacetylcholine （ACh） on cell membrane and cell survival rate of cultured primitive rat hippocampal neurons. Methods After isolation and primary culture, hippocarnpal neurons were exposed to ACh at different concentrations. The subsequent changes in the membrane ultrastructure of neurons and MTT metabolic rate were observed by atomic force microscope and MTT assay respectively. Results Normal neurons displayed smooth membrane surface, while the neurons treated with ACh, in contrast, presented degenerative changes characterized by coarse membrane surface with holes （ diameter： 100 nm-1μm,depth： 100-400 nm）. As the treatment time was prolonged and ACh concentration increased, the changes became more evident. MTT metabolic rate was significantly decreased under the induction of ACh in a dose-dependent manner （P〈0.05）. Conclusion ACh may hurt neuron membrane to some extent, and decrease cell survival rate in the end.