小鼠急性致痫间后海马活化素βA基因表达的变化与意义初探

The changes of activin βA gene in the hippocampus of mice following pilocarpine-induced seizures

目的探讨小鼠癫持续状态(Statusepilepticus,SE)后海马活化素βA基因的表达与意义。方法采用毛果芸香碱诱导的SE小鼠模型,应用逆转录聚合酶链反应(RTPCR)及原位杂交观察SE后海马活化素βA基因表达的动态变化;应用尼氏染色观察海马病理形态结构的变化。结果SE后3h海马活化素βAmRNA表达即显著增高,6h达高峰,持续至约24h后开始回落,48h恢复近正常水平;活化素βAmRNA表达最先在海马CA2及DG区上调,高峰时CA3区亦见明显表达,48h后仅CA2区仍可见阳性表达;海马活化素βAmRNA水平与神经元抗损伤力有关。结论毛果芸香碱诱导的SE能明显上调海马活化素βAmRNA表达,其水平的上调可能有助于增强海马神经元抗兴奋性损伤的能力。

Objective To investigate the expression and its value of activin βA gene in the mouse hippocampus after status epilepticus（SE）. Methods The pilocarpine（PC）-induced mouse SE model was used. RT-PCR and hybridization in situ were used to observe the dynamical expression pattern of activin βA. Cresyl violet staining was used to study the changes of hippocampal pathology. Results Activin βA mRNA in hippocampal tissue quickly went up to a significant level at 3h after SE, reached the peak at 6h after SE, and maintained this level about 24h after SE. Then, the level of activin βA mRNA gradually declined. At 48h after SE, it went back to near base line. The dramatic upregulation of βA mRNA appeared first in the hippocampus CA2 and DG regions, and was also seen in the CA3 region at the peak. At 48h after SE, only CA2 region still had detectable positive signals of βA mRNA. The levels of regional βA mRNA in hippocampus positively related to neuronal resistance to excitotoxic injury. Conclusions PC-induced SE can strongly upregulate the hippocampal expression of activin βA mRNA, which may contribute to hippocampal neurons against excitotoxic injury following epileptic insults.