耐药性杏仁核点燃癫痫模型海马组织中γ-氨基丁酸受体表达变化

Decreased expression of Y-aminobutyric acid receptor in the hippocampal tissues of pharmacoresistant temporal lobe epileptic rats

目的建立多药耐药性癫痫模型，观察海马组织y-氨基丁酸（GABA）受体表达变化从而探讨其在耐药性杏仁核点燃癫痫形成中的作用。方法选用Wistar大鼠100只制作慢性杏仁核点燃癫痫模型，模型制作成功（n=52）后用经典抗癫痫药苯妥英钠和苯巴比妥进行筛选，根据大鼠对苯妥英钠和苯巴比妥的反应区别出耐药癫痫大鼠（n=8）及药物敏感大鼠（n=8），然后处死动物留取脑组织标本，用免疫组织化学染色方法观察海马组织内GABAA受体表达变化，用蛋白质印迹法检测GABAA受体含量，观察耐药癫痫大鼠和药物敏感大鼠之间的不同。结果耐药癫痫性颞叶大鼠海马细胞变性坏死，排列紊乱，结构特征消失；耐药性颞叶癫痫大鼠海马组织内GABAA受体阳性表达细胞的灰度值（141．15±14．72）比药物敏感大鼠增高（92．56±5．17；t=3．380，P=0．006）；蛋白质印迹方法提示受体条带变淡变窄，蛋白含量明显减少（0．38±0．08），与药物敏感大鼠（0．88±0．18）比较，差异具有统计学意义（t=5．420，P=0．002）；但两组间GABAA受体阳性细胞数百分率比较差异无统计学意义。结论耐药性颞叶癫痫大鼠海马组织内GABA受体表达明显减少，这可能在耐药性颞叶癫痫的形成过程中发挥部分作用。

Objective To establish a multi-drug resistant model of temporal lobe epilepsy, and to observe the changes of T-aminobutyric acid （GABA） receptor expression in the hippocampal tissues so as to explore its effects in pharmacoresistant epileptogenesis. Methods One hundred rats were selected to prepare the amygdaloid kindled model of epilepsy by chronic stimulation of amygaloid basal lateral nucleus. After the kindled model of epilepsy was prepared successfully（n = 52） , pharmacoresistant epileptic rats were selected according to their response to the phenobabital and phenytoin. The selected pharmacoresistant epileptic rats （n = 8）were sacrificed and the hippocampus was removed to determine the GABA receptor expression, and the same number of pharmaeosensitive epileptic rats was used as control. Results The pharmaeoresistant epileptic rats displayed degenerative and necrotic hippocampal neurons. The arrangement of hippocampal neurons was disordered, and the structural characteristics of the arrangement of the hippocampal neurons disappeared. The gray values of GABAA-positive neurons in the hippocampal tissues （ 141.15 ± 14. 72） increased significantly compared with the phannacosensitive epileptic rats （92. 56 ±5.17; t = 3. 380, P = 0. 006）. Western blot method demonstrated that the band of GABAA became narrowed and thin. The relative quantity of GABAA in the hippocampal tissues （0. 38 ± 0. 08） decreased significantly as compared with the pharmacosensitive epileptic rats （0. 88 ± 0. 18） . A significant difference was observed （ t = 5. 420, P = 0. 002）. Conclusions GABA receptor expression might be decreased in the hippocampal tissues of pharmacoresistant epileptic rats. It might play a certain role in the formation of pharnmacoresistant epilepsy.