大鼠颞叶癫痫发作后学习记忆障碍与海马神经元内游离钙离子浓度变化的相关性研究  

Correlation between learning and memory impairment and the changes of intracellular free Ca^(2+) concentration in hippocampal neurons after temporal lobe epilepsy in rats

作　　者：钱若兵[1] 傅先明[1] 牛朝诗[1] 汪业汉[1] 魏建军[1] 鲁明[1] 王林[1] 

机构地区：[1]安徽医科大学附属省立医院神经外科安徽省立体定向神经外科研究所,合肥230001

出　　处：《中华神经医学杂志》2007年第11期1104-1108,共5页Chinese Journal of Neuromedicine

基　　金：安徽省高等学校自然科学研究项目(2005KJ345zc;2005KJ359zc)

摘　　要：目的探讨大鼠颞叶癫痫发作后不同时间段学习记忆障碍程度与海马神经元内游离钙离子([Ca^(2+)]i)浓度变化的相关性。方法立体定向方法建立大鼠颞叶癫痫模型后用Morris水迷宫实验评价不同时间段大鼠学习记忆障碍程度;利用钙离子探针Fluo-3/AM在激光扫描共聚焦显微镜下检测癫痫发作后不同时间段海马神经元内[Ca^(2+)]i的变化。结果大鼠颞叶癫痫发作后均出现不同程度的学习记忆障碍,随发作时间的延长逐渐加重,发作2月后达到高峰。颞叶癫痫发作后右侧海马神经元内[Ca^(2+)]i的荧光强度明显升高,6 h达到高峰,发作2月内保持在较高水平,与正常对照组和注射生理盐水组比较有显著性差异(P<0.05),而3月后则有下降并低于正常对照组的趋势;对侧海马神经元内[Ca^(2+)]i的荧光强度高于正常对照组和注射生理盐水组,但低于右侧海马神经元内[Ca^(2+)]i的荧光强度。结论大鼠颞叶癫痫发作后的学习记忆障碍随发作时间延长而加重,发作2月后达到最严重,与海马神经元内[Ca^(2+)]i变化具有一定的时间相关性。Objective To explore the correlation between learning and memory impairment and the changes of intracellular flee Ca^2＋ concentration （[Ca^2＋]i） in hippocampal neurons at different periods after seizures of temporal lobe epilepsy （TLE） in rats. Methods The kainic acid-induced TLE models in Spragne-Dawley （SD） rats were established with stereotactic techniques. The extent of learning and memory impairment was evaluated by the Morris water maze test; changes of [Ca^2＋]i in hippocampal neurons at different periods were measured with Ca^2＋-sensitive fluorescent probe Fluo-3/AM and laser scanning confocal microscope （LSCM）. Results All rats developed learning and memory impairment to the certain extent, aider seizures of TLE induced by kainic acid injection into the right hippocampus, which deteriorated with seizures in a time-dependent manner and rose to the climax 2 months later aider seizures. The fluorescence intensity of [Ca^2＋]i in right hippocampal neurons increased evidently after seizures of TLE： it rose to its climax at 6 h, maintaining a comparatively high level within the 2 months after seizures [its comparison with the normal control and normal saline ingection group was significant （P〈0.05）], but began to decrease 3 months later atter seizures, tending to be lower than that of the normal control group; the fluorescence intensity of [Ca^2＋]i in contralateral hippocampal neurons was higher than that of the normal control and normal saline injection groups, but still lower than that of the right hippocampal neurons. Conclusion Learning and memory impairment of the rats atter seizures of TLE become aggravated in a time-dependent manner with seizures and culminates at 2 month, which has some time correlation with changes in [Ca^2＋]i of hippocampal neurons.

关 键 词：颞叶癫痫 学习记忆障碍 钙离子 

分 类 号：R742.1[医药卫生—神经病学与精神病学]