星形胶质细胞条件培养基对培养海马神经元GluR2和PICK1 mRNA表达的调控

目的 探讨癫痫发病过程中,星形胶质细胞对神经元AMPA受体亚单位表达的调节机制.方法 收集谷氨酸刺激的星形胶质细胞条件培养基,作用于培养的海马神经元,用RT-PCR方法检测神经元GluR2和PICK1 mRNA表达的变化.结果 在星形胶质细胞条件培养基作用2h、8h、12h后,培养的海马神经元GluR2mRNA表达明显下降,而PICK1 mRNA表达则升高,与对照组相比,差异有显著意义(P＜0.05).离子型谷氨酸受体拮抗剂D-AP5和CNQX不能完全阻断条件培养基的作用.结论 在癫痫发病过程中,星形胶质细胞激活能通过上调PICK1的表达,实现下调神经元AMPA受体GluR2亚单位的表达.

REGULATION OF ASTROCYTIC CONDITIONAL MEDIUM ON THE EXPRESSIONS OF GluR2 AND PICK1 mRNA IN CULTURED HIPPOCAMPAL NEURONS

Objective To explore the regulating mechanism of the astrocytes on the expression of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) subunit in epileptogenesis. Methods The astrocytic conditional medium (ACM) was collected after being stimulated by glutamate, and then ACM was added to the cultured hippocampal neurons. The expression changes of neuronal GluR2 and protein interacting with C-kinase-1 (PICK1) mRNA were detected by RT-PCR. Results In the cultured hippocampal neurons, the GluR2 mRNA expression was significantly decreased at the 2nd, 8th, and 12th hours after the administration of ACM compared with that in the control group (P<0.05). However, the PICK1 mRNA expression was significantly increased at the same time points after the administration of ACM compared with that in the control group (P<0.05). The ionotropic glutamate receptor antagonists D-AP5 and CNQX could not fully block the action of ACM. Conclusion In epileptogenesis, the activation of astrocytes can down regulate the expression of neuronal AMPARs GluR2 subunit by up regul