听源性惊厥点燃诱导新皮质内c-fos和BDNF变化的研究

CHANGES OF EXPRESSION OF c-fos GENE AND BDNF IN NEOCORTEX INDUCED BY AUDIOGENIC KINDLING

为探讨前脑结构参与听源性惊厥点燃过程的神经化学机制 ,本研究以 c-fos基因表达作为神经元功能活动的标志 ,采用免疫细胞化学方法 ,对新皮质内参与听源性惊厥点燃过程的神经元的分布状况进行了观察 ,并对相关区域内脑源性神经营养因子表达水平的变化进行了分析。结果显示 ,单次听源性惊厥发作后 ,新皮质内仅有少量散在的 c-fos阳性神经元存在 ;听源性惊厥点燃后 ,额、顶、枕及颞叶皮质内出现大量 c-fos阳性神经元。点燃后额叶及顶叶皮质内脑源性神经营养因子免疫阳性产物的校正光密度值显著增高。结果表明 ,新皮质内大量神经元参与听源性惊厥点燃过程 ,脑源性神经营养因子表达增强很可能是其中的机制之一。

To identify the neurochemical mechanisms of the audiogenic kindling in the forebrain structures, the expression of c fos gene, a marker of neuronal activity, and the level of brain derived neurotrophic factor (BDNF) in the neocortex were studied after single and kindled audiogenic seizure with immunocytochemistry method. The results showed that after single seizure, there were few c fos positive neurons found in neocortex. After kindled seizure there were lots of c fos positive neurons in the frontal, parietal, occipital and temporal cortices. Meanwhile, the corrected optic densities (COD) of BDNF immuoreactivities in the frontal and parietal cortices were significantly increased in kindled rats. The results indicated that there are numerous neurons in the neocortex participated in the process of audiogenic kindling. The enhancement of the expression of BDNF in the neocortex may be involved in this process. (Figures 1～6 on plate 51)