反复惊厥对P77PMC大鼠海马结构及其惊厥行为的影响  

Effects of recurrent audiogenic seizures on hippocampal structure and seizure behavior of P77PMC rats

作　　者：赵世刚[1] 姜玉武[1] 罗强[1] 吴希如[1] 

机构地区：[1]北京大学第一医院儿科神经组

出　　处：《中华儿科杂志》2003年第1期21-24,共4页Chinese Journal of Pediatrics

基　　金：国家自然科学基金资助项目 ( 39670 2 65 )

摘　　要：目的　探讨海马苔藓状纤维 (mossyfiber,MF)发芽在癫发生发展病理生理机制中的作用。方法　采用Timm′s硫化银染色法和尼氏染色法 ,对反复惊厥过程中不同阶段遗传性癫易感大鼠模型———P77PMC大鼠海马的结构以及惊厥行为的改变进行观察研究。结果　反复多次听源性惊厥样发作可导致P77PMC大鼠海马CA1区的部分神经元缺失和海马齿状回内分子层出现明显的MF发芽表现 ;并能使其听源性惊厥样发作的潜伏期显著缩短 ,而惊厥发作的持续时间明显延长。结论　在遗传性听源性惊厥 ,这种脑干起源但迅速泛化为全身性惊厥发作的癫动物模型 ,也有海马内神经元缺失和MF突触重组的表现。听源性惊厥易感大鼠在经历足够多次的反复惊厥发作后 ,可发生海马苔藓状纤维发芽和神经元缺失 ;另外单纯惊厥的反复发作还能导致P77PMC大鼠惊厥加剧、惊厥易感性增高。在反复听源性惊厥过程中 ,P77PMC大鼠惊厥易感性增高的行为改变在海马发生明显的结构性变化之前就已发生 。Objective To investigate the functional role of hippocampal mossy fiber sprouting in the pathophysiologic mechanism of initiation and propagation of epilepsy. Methods The authors examined hippocampal mossy fiber synaptic reorganization and the changes of hippocampal neurons in P77PMC rats at different stages in the course of recurrent seizures using Timm′s method of silver sulfide staining and Nissl staining and observed the effects of recurrent audiogenic seizures (AGSs) on seizure behavior of P77PMC rats. Results Frequent recurrent AGSs could cause neuronal loss in CA 1 region of hippocampus and hippocampal mossy fiber sprouting got into the inner molecular layer of dentate gyrus in P77PMC rats, and could decrease the latency of Ⅳ/Ⅴ grade of AGSs, increase the durations of AGSs. The mean A of CA 1 region of hippocampus in Nissl staining after 50 times of AGSs was 35.3±0.8, which was markedly lower than that of the control (44.1±0.5; F=333.89, P<0.001). The mean A of the inner molecular layer of dentate gyrus in Timm′s staining after 50 times of AGSs was 49.3±4.6, which was markedly higher than that of the control (26.8±1.7; F=76.83, P<0.001). After 30 and 50 times of AGSs, the latent periods of Ⅳ/Ⅴ grade of AGSs were 12±8 (t=3.805; P<0.02) and 17±7 (t=5.927; P<0.002) seconds shorter than the initial period of stimulation respectively on average, and the durations of AGSs were 19±18 (t=2.644; P<0.05) and 10±7 (t=3.780; P<0.02) seconds longer. Conclusion Hippocampal mossy fiber sprouting and neuronal loss not only presents in limbic seizure, but also in AGS, the seizure can be initiated in brainstem but rapidly generalized;in AGS-prone rats, recurrent AGSs can cause mossy fiber synaptic reorganization and neuronal loss in hippocampus, and can also enhance seizure susceptibility of P77PMC rats. In the course of recurrent AGSs, enhanced seizure susceptibility happened before hippocampal mossy fiber sprouting. Their temporal relationships indicate that the anatomical changes may be prec

关 键 词：反复惊厥 P77PMC 大鼠 海马结构 惊厥行为 癫痫 神经纤维疾病 疾病遗传易感性 统计学 尼氏染色法 

分 类 号：R742.1[医药卫生—神经病学与精神病学]