Abstract:

Objective  To investigate the expression changes of G-protein-coupled receptor kinase-interacting protein 1 (GIT1) in lithium-pilocarpine-induced epileptic rat model and explore its role in the genesis and development of epilepsy.  Methods  The lithium-pilocarpine-induced model of status epilepticus (SE) was established in 42 specific pathogen free (SPF) male adult Wistar rats, and those rats were randomly divided into control group and 6 epilepsy groups (1, 3, 7, 14, 30, 60 d after SE). The expression of GIT1 mRNA was detected by fluroescent quantitative polymerase chain reaction (PCR), while the expression of GIT1 protein was examined by Western blotting and immunohistochemistry was applied to test the expression of CA1 region, dentate gyrus and parahippocampal cortex in rat hippocampus at different time points.  Results  GIT1 mRNA level rised in acute phase on 1st and 3rd day after SE (P = 0.012, 0.002), then increased continously in latency on 7th and 14th day (P = 0.003, 0.001), and reached the peak in chronic phase on 30th and 60th day (P = 0.000, for all). GIT1 protein expression rised in acute phase and increased continously in chronic phase, but there was no significant difference compared with control group (P > 0.05, for all). Then, it reached the peak in chronic phase (P = 0.000, for all). Until the 30th day, the GIT1 expression of CA1 region, dentate gyrus and parahippocampal cortex in the hippocampus of rats in 6 epilepsy groups was significantly higher than that of control group (P = 0.000, for all).  Conclusions  The up-regulated expression of GIT1 in the hippocampus of epileptic rat was probably involved in the formation process of chronic epilepsy by regulating cytoskeleton dynamic regrouping to influence excitatory neural networks.

Key words: GTP-binding proteins, Receptors, G-protein-coupled, Epilepsy, Hippocampus, Disease models, animal

摘要：

目的 观察G 蛋白耦联受体激酶相关蛋白1（GIT1）在氯化锂-匹罗卡品致痫模型大鼠海马组织中的表达变化，以探讨GIT1 在癫痫发生发展过程中的作用机制。方法 共42 只无特定病原体级成年雄性Wistar 大鼠，制备氯化锂-匹罗卡品致痫模型，随机分为对照组和癫痫组（癫痫发作后1、3、7、14、30、60 d），荧光定量聚合酶链反应、Western blotting 法和免疫组织化学染色检测各观察时间点大鼠海马组织GIT1 表达变化。结果 癫痫组大鼠GIT1 mRNA 自癫痫持续状态后急性期第1 和3 天即升高（P = 0.012，0.002），至潜伏期第7 和14 天持续升高（P = 0.003，0.001），至慢性期第30 和60 天达峰值水平（均P = 0.000）；GIT1 蛋白自急性期即升高，慢性期持续升高，但与对照组相比，差异未达统计学意义（均P >0.05），至慢性期达峰值水平（均P = 0.000）。至慢性期第30 天时，癫组大鼠海马CA1 区、齿状回和海马旁皮质GIT1 蛋白表达水平均高于对照组（P = 0.000）。结论 癫痫大鼠海马组织GIT1 表达上调，可能通过调节细胞骨架动态重组而影响兴奋性神经网络，从而参与癫痫的发生。

关键词: GTP 结合蛋白质类, 受体, G-蛋白偶联, 癫痫, 海马, 疾病模型, 动物