匹罗卡品致痫诱发大鼠齿状回颗粒细胞GAP-43mRNA表达

Growth-associated protein mRNA expression is induced in the granule cells of the dentate gyrus following pilocarpine-induced seizures in rats

目的 研究边缘系统癫痫发作后海马颗粒细胞生长相关蛋白（GAP-43）基因表达变化。方法 建立匹罗卡品急、慢性癫痫模型,用原位杂交方法定量检测不同时间点海马颗粒细胞GAP-43mRNA表达。结果 对照组颗粒细胞几乎不表达GAP-43mRNA,匹罗卡品致病后6～12h颗粒细胞表达GAP-43mRNA增高,15～30d呈现第2次高峰。结论 成年大脑海马颗粒细胞在致痫后发生可塑性变化,GAP-43mRNA表达是癫痫大鼠大脑结构性重组（颗粒细胞苔藓纤维出芽）的重要分子机制。

Objective To determine whether granule cells can be induced to express mRNA of an axonal growth-associated protein(GAP-43) after limbic seizure, which can induce sprouting of granule cell mossy fibers. Methods The pilocarpine-induced model of acute and chronic seizures was used to evaluate the time course of the granule cells GAP-43 mRNA expression by quantitative in situ hybridization. Results We found that 6~12 h af-ter pilocarpine injection, GAP-43 mRNA was induced in granule cells which normally do not express it and re-mained elevated above control level for at least 30 days. The second peak of expression was detected during 15~30 day in the granule cell layer but not in CA3 or CA1 region. Conclusion Those results demonstrate that CAP-43 gene expression can be altered in neurons in the adult brain. Induction of GAP-43 mRNA expression in the granule cells may be important for the sprouting of mossy fibers and may also be one of the molecular mechanisms underly-ing structural remodeling in epilepsy.