Dynamics of microglial cells in the brain of Ihara epileptic rats in accordance with seizure progress

Ihara癫痫大鼠脑内小胶质细胞随癫痫发作进展的动态变化

基本信息

批准号：
13670212
负责人：
AMANO Shigeru
金额：
$ 2.11万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2002
项目状态：
已结题

项目摘要

It is supposed that the significance of glial reaction in epileptic brain might be unveiled by clarify the localization and degree of gliosis in epileptic mutant, Ihara epileptic rat. Possible function of microglia cells in the rat experienced epileptic seizures was studied by investigation of localization and degree of microglial reaction in IER brains with immunohitochemical examination using OX-42 antibody. Density of OX-42 positive microglial cells was investigated in the portions of cerebral cortex, endorrhinal cortex, thalamus, amygdale, hippocampus and dentate gyrus in IERs and non-epileptic control rats.In IERs, rats of 2 months old, microglial with OX-42 positive reaction was increased in mild or moderate degree in the portions of the brain described above, particularly in the hippocampus, the thalamus and the amygdala. In rats of 6 months and 10 months old, marked increase in OX-42 positive microglia was found in hippocampus, thalamus and amygdala in addition to the whole brain. Microglia cells with OX-42 positive reaction, which possessed short and thick processes, were thought to be an activated microglial of amoeboid type.It is suggested that microglial activation was induced by epileptic activities in the brain of IER, and then cytokines released by activated glial cells have some influences to the functions of neurons or glial cells. Because increased activated microglia was shown in the portions of hippocampus, thalamus and amygdala from young age, those areas ware thought to have significant role for the epileptogenesis. Furthermore, it is safely assumed that epileptic activities influenced not only in the hippocampus, thalamus and amygdala but also in other portions of the brain from the finding of diffuse increase in OX-42 positive cells in the whole brain of IER.

推测通过阐明癫痫突变体伊原癫痫大鼠神经胶质细胞增生的定位和程度，可能揭示癫痫脑中神经胶质细胞反应的意义。通过使用 OX-42 抗体进行免疫组织化学检查，研究 IER 大脑中小胶质细胞反应的定位和程度，研究了经历癫痫发作的大鼠中小胶质细胞的可能功能。检测IER和非癫痫对照大鼠大脑皮层、内嗅皮质、丘脑、杏仁核、海马和齿状回部分OX-42阳性小胶质细胞的密度。在IER中，2月龄大鼠，OX-42阳性小胶质细胞42 阳性反应在上述大脑部分有轻度或中度增加，特别是海马体、丘脑和杏仁核。在6个月和10个月大的大鼠中，除全脑外，海马、丘脑和杏仁核中的OX-42阳性小胶质细胞也显着增加。 OX-42阳性反应的小胶质细胞具有短而粗的突起，被认为是阿米巴型小胶质细胞的活化。提示小胶质细胞的活化是由IER脑内的癫痫活动诱导，然后被激活的小胶质细胞释放细胞因子。胶质细胞对神经元或胶质细胞的功能有一定的影响。由于从年轻时起，海马体、丘脑和杏仁核部分就显示出活化的小胶质细胞增加，因此这些区域被认为对癫痫发生具有重要作用。此外，根据 IER 全脑 OX-42 阳性细胞弥漫性增加的发现，可以安全地假设癫痫活动不仅影响海马、丘脑和杏仁核，而且还影响大脑的其他部分。