海马神经元激活物致大鼠大脑皮质和海马γ-氨基丁酸受体的表达

Expression of GABA_A receptor in hippocampal neurons and cortex in epileptic rats induced by activited hippocampal neurons products

目的 观察大鼠海马神经元在激活物作用下γ-氨基丁酸（GABA。）受体的表达，进一步探讨癫痫发病机制。方法 将大鼠海马神经尢被戊四氮（PTZ）作用后的激活物（实验组）及无血清培养基（对照组）注入大鼠侧脑室后观察其行为、脑电图（EEG）及脑组织GABA，受体表达的变化。结果 实验组大鼠注射后15～30min出现Ⅱ～Ⅲ级惊厥反应，EEG呈短程中高幅尖波、尖慢复合波；对照组的行为及EEG未见异常；各时点实验组大鼠脑组织GABA、免疫反应阳性细胞表达明显低于对照组（均P〈0．05），对照组GABA，免疫反应阳性细胞广泛分布于大脑皮质、海马回、齿状回。结论 海马神经元激活物具有明显致痫作用，其致痫效应与GABAA受体含量下降有关。

Objective To investigate the expression of GABAA receptor in the process of activation of hippocampal neurons and explore the epileptogenesis. Methods The activated hippocampal neuron products （experiment group ） and the serum-free-medium （control group ） were injected into rat＇s lateral ventricle, respectively, then we observed the behaviors, electroencephalographic （EEG） and immunochemical changes of GABAA receptor in rats. Results l0 - 30 rain after administration of pentetrazole （ PTZ）-activated hippocampal neuronal products, Ⅱ-Ⅲ class epileptic behaviors were found in the experiment group. EEG showed many short distance moderate amplitude sharp waves, sharp and slow wave complex. The behaviors of rats and EEG results were normal in the control group. GABAAreceptor positive cells extensively spread over cerebral cortex, hippocampal CAA and dentate gyrus in the control group, and the expression of GABAA receptor significantly decreased in the experiment group. Conclusion Activated hippocampal neuronal products could induce epilepsy. One of its mechanisms might be related to the decrease of GABAA content.