慢性癫痫模型海马神经元内钙稳态和钙动力学的长期变化  

Study on the long-term change of calcium homeostasis and kinetics in chronic epilepsy model

作　　者：吴伟[1] 迟兆富[1] 刘学伍[1] 赵秀鹤[1] 徐宁[2] 赵鲁鸣[2] 

机构地区：[1]山东大学齐鲁医院神经内科,济南250012 [2]山东中医药大学针灸推拿学院

出　　处：《中华神经科杂志》2008年第10期695-698,共4页Chinese Journal of Neurology

基　　金：山东省卫生厅资助项目（HZ047）

摘　　要：目的探讨海马神经元内长期钙离子（[Ca^2＋]i）和动力学变化在癫痫发生机制中的作用。方法建立氯化锂-匹罗卡品慢性癫痫模型，于致痫后6h和1、3、7、14、30d不同时间点应用激光共聚焦显微镜观察离体海马神经元内[Ca^2＋]i的变化以及谷氨酸负荷后神经元内[Ca^2＋]i恢复速度的变化。结果正常对照组大鼠急性分离海马神经元[Ca^2＋]i为（95．4±22．1）nmol／L，致痫后急剧升高至（867．6±35．2）nmol／L，第7天降低至（292．8±18．3）nmol／L，此后持续在此水平，30d后降至（220．8±17．6）nmol／L，仍高于对照组（t=12．55，P〈0．01）；正常对照组大鼠92％的海马神经元内[Ca^2＋]i处于正常范围内（25—150nmol／L），致痫后6h，所有神经元[Ca^2＋]i均有升高，并且85％的神经元高于500nmol／L，致痫7、14、30d后分别有75％、60％、52％的神经元[Ca^2＋]i高于正常值，但高于500nmol／L者逐渐减少；经接触5μmol／L谷氨酸人工脑脊液2min后，对照组神经元可在（9．5±3．4）min内恢复至基线水平，而急性期、潜伏期、慢性期的癫痫神经元均存在明显延迟（t=5．08、4．56、4．21，P〈0．01）。结论氯化锂-匹罗卡品致痛后可造成海马神经元内长期的[Ca^2＋]i和钙动力学改变，该种长期可塑性改变在慢性癫痫模型的诱发和维持中起着重要作用。Objective To study the role of calcium homeostatic and kinetics in the epileptogenesis activity. Methods Hippocampal neurons were acutely isolated from controls and status epilepticus （SE） models induced by lithium-pilocarpine at different time point. The [ Ca^2 ＋ ] i levels were detected by laser scanning confocal microscope. And the ability to restore resting [ Ca^2＋ ] i levels after a brief exposure to 5 μmol/L glutamate in control and epileptic neurons were evaluated. Results The [ Ca^2＋ ] i level of acute separated hippocampal neurons in the control rats was （ 95.4 ±22. 1） nmol/L. After injection of lithium pilocarpine, the [ Ca^2＋] i level in hippocampal neurons increased dramatically to （ 867. 6 ± 35.2 ） nmol/L, and decreased to （292. 8 ± 18.3 ） nmol/L on the 7th day, lasting for about 30 days （（ 220. 8 ± 17.6） nmol/L）, it is higher than that in the control group （t = 12. 55, P 〈 0. 01 ）. The distribution of neuronal [ Ca^2＋ ]i showed that 92% of control neurons were in the normal range of [ Ca^2＋ ] i level （25--150 nmol/L） ; After 6 hours, however [ Ca^2＋ ]i levels of all SE neurons increased, and 85% of which were higher than 500 nmol/L; After 7, 14 and 30 days, there were 75%, 60% and 52% of SE neurons still manifested an elevated [ Ca^2＋ ] i level, but less than 500 nmol/L. After the exposure to 5 μmol/L glutamate treatment for 2 minutes, [ Ca^2＋ ]i of the control neurons restored to baseline values in （9. 5 ± 3.4） minutes, whereas the SE rats of acute, latent and chronic phases did not （t = 5.08, 4. 56, 4. 21, all P 〈 0.01 ）. Conclusion Lithium-pilocarpine induced epilepsy causes a long-term alteration of calcium homeostatic mechanisms of hippocampus neurons, which may play an important role in the development and maintenance of spontaneous recurrent seizures.

关 键 词：癫痫 海马 神经元 钙 疾病模型 动物 

分 类 号：R686[医药卫生—骨科学]