癫痫大鼠海马NMDA受体亚基NR2A和BDNFmRNA水平的检测

目的通过锂一匹罗卡品癫痫模型（ithium—pilocarpine seizures rats model of epilepsy，LPS），研究NMDA受体亚基NR2A、BDNF mRNA的表达，探讨NR2A、BDNF在LPS中的作用。方法建立氯化锂-匹罗卡品大鼠模型，运用原位杂交技术检测致痫后各组不同时间点海马CAI、CA3及DG区NR2A与BDNF mRNA的表达。结果LPS海马NR2A、BDNF mRNA在各观察时间点及部位模型组与正常对照组比较均有明显上调，且有显著统计学差异（P〈0．05）。模型组NR2A mRNA的表达上调7d达峰值（P〈0．05）；而BDNF mRNA表达上调14d达峰值。VPA干预组NR2A mRNA在大鼠海马不同时间及部位（除1d的CA3区）的表达较模型组明显下调（P〈0．05）；BDNF mRNA在大鼠海马不同时间及部位（除28d的DG区）的表达较模型组明显下调（P〈0．05）。结论锂－匹罗卡品腹腔注射可诱导大鼠海马NR2A和BDNF mRNA的表达明显上调；NR2A mRNA表达的增强可能是诱导调控BDNF mRNA表达增强的重要机制之一，说明NMDA受体亚基NR2A可能成为抑制癫痫发作的新靶点。

Expression of NR2A mRNA and BDNF mRNA in Hippocampaus of LPS

Objective The study was aimed to investigate mRNA expression of hippocampal NMDA receptor subunits NR2A and BDNF in lithium-pilocarpine seizures rat model of epilepsy （LPS）, and explore the effect of NR2A and BDNF in LPS. Methods Clean class male SD rats, except the 6 rats of normal control group （ group A）, were intraperitoneally injected with pilocarpine to make models. The surviving rats were randomly divided into five groups： model group （ group B） and VPA group （ group C） . Each group was randomly divided into 4 subgroups, correspondingly to the time points of 1, 7, 14, and 28 days after kindling. Each subgroup was composed of 6 rats. The kindled model of LPS was established by intraperitoneal injection of lithium-pilocarpine to induce status of epilepticus. The rats were intragastrically administrated with medicines or 0. 9% sodium chloride, and 15min later the models were successfully build, followed by administration every 24 hours. The frequency and grade of spontaneously recurrent seizures （SRS） were daily observed within 9 ： 00 ~ 12 ： 00 and 14 ： 00 - 17 ： 00. The mRNA expression of hippocampal NMDA receptor subunits NR2A and BDNF were detected by in situ hybridization （ISH） . Experimental resuhs were analyzed with statistical software （ SPSS 13.0） . Results Expression of mRNA of NR2A and BDNF was observed in pyramidal and granular cells in all hippocampal subfields. Expression of NR2A and BDNF were significantly increased in epilepsy group compared to normal group （P 〈 0.05） . The highest expression of NR2A and BDNF was reached respectively at 7d and 14d. Compared with model group, the mRNA level of hippocampal NR2A and BDNF was significantly decreased in VPA group （P 〈 0. 05） . Conclusion Lithium-piloearpine intraperitoneally injected can significantly upregulate NR2A and BDNF expression, indicating a regulatory mechanism of BDNF mRNA possibly related to epilepsy. Expression of NR2A mRNA may lead to increase of BDNF expression, implying that NR2A can