中毒剂量谷氨酸引起大脑皮质神经细胞的钙振荡及其机制探讨  

Ca^(2+) OSCILLATION OF CEREBRAL CORTICAL NEURONS INDUCED BY GLUTAMATE OF TOXIC DOSE AND ITS MECHANISM

作　　者：邢虹[1] 何其华[2] 于桂芬[1] 袁兰[2] 徐家[2] 吴本 

机构地区：[1]北京医科大学生物物理系,北京100083 [2]北京医科大学医学分析中心,北京100083

出　　处：《中国应用生理学杂志》1999年第4期294-297,共4页Chinese Journal of Applied Physiology

基　　金："九五"国家医学科技攻关项目

摘　　要：目的和方法：本文观察中毒剂量谷氨酸对大鼠大脑皮质神经细胞内Ｃａ２＋ 含量变化的影响，并对其机制进行探讨。将１ ｍ ｍｏｌ／Ｌ谷氨酸加入大脑皮质神经细胞培养液中通过激光共聚焦扫描显微镜（ｌａｓｅｒ ｃｏｎｆｏｃａｌｓｃａｎｎｉｎｇ ｍｉｃｒｏｓｃｏｐｅ，ＬＣＳＭ） 观察细胞内Ｃａ２＋ 含量的变化。结果：①１ ｍ ｍｏｌ／Ｌ谷氨酸作用后在观察的８６ 个细胞中，７１ ％ 的细胞内游离Ｃａ２＋ 浓度发生钙振荡，发生钙振荡的波型均为尖峰型：②在抑制细胞内钙库释放后加入１ ｍ ｍｏｌ／Ｌ 谷氨酸，细胞内Ｃａ２＋ 浓度上升，但没有产生钙振荡；而抑制细胞外Ｃａ２ ＋ 内流后加入１ ｍｍｏｌ／Ｌ 谷氨酸，细胞内Ｃａ２ ＋ 发生钙振荡，但振荡幅度逐渐下降直至振荡消失。结论：中毒剂量谷氨酸引起神经细胞钙振荡形成的可能机制是：细胞内钙库的释放和摄取是Ｃａ２ ＋ 发生振荡的必要条件，而振荡的维持则依赖于细胞外Ｃａ２＋Aim and methods: The purpose of present study was to observe temporal changes of intracellular Ca 2+ induced by 1 mmol/L glutamate and explore its mechanism. Temporal changes of intracellular Ca 2+ was measured by laser confocal scanning microscope. Results: ①In cerebral cortical neurons, 1 mmol/L glutamate caused Ca 2+ oscillation found in 71% neurons (86 cells in total) and wave type as spiking. ②After inhibition of the release in intracellular Ca 2+ store, [Ca 2+ ]i raised, but wasn't calcium oscillation. On the contrary, when added 1 mmol/L glutamate following inhibition of the extracellular Ca 2+ inflow, calcium oscillation was produced in cells, but the oscillation amplitude progressively decreased until oscillation disappeared. Conclusion: The possible mechanism of Ca 2+ oscillation (in neurons induced by glutamate of toxic dose) is that the release and uptake of Ca 2+ store are involved in Ca 2+ oscillation and Ca 2+ oscillation is dependent on the Ca 2+ influx from extracellular space.

关 键 词：钙离子 谷氨酸 中毒剂量 钙振荡 大脑皮质 

分 类 号：R743.310.2[医药卫生—神经病学与精神病学]