星形胶质细胞与GnRH神经元共培养可通过谷氨酸受体介导促进GnRH神经元分泌

The Secretion of GnRH Neuron can be Enhanced by the Coculture with Astrocyte in vitro Via the Change in GluR

目的探讨下丘脑促性腺激素释放激素(GnRH)神经元与星形胶质细胞共培养对GnRH神经元的影响及其可能的相关机制。方法利用Transwell共培养系统,将GnRH神经元细胞株GT1-7与原代星形胶质细胞共培养10d。免疫组织化学法检测GnRH神经元中谷氨酸受体(GluR)的分布,蛋白免疫印迹法检测GluR在GnRH神经元中的表达,并分别通过高效液相色谱法和酶联免疫吸附法检测培养上清中的谷氨酸(Glu)和GnRH的浓度变化。结果共培养组的GnRH神经元发生mGluR5和GluR1/2/3/4从胞质到胞核的移位,在胞核中的表达较单纯GT1-7培养组显著增加(P<0.05),且Western-blot检测与免疫荧光检测结果一致。HPLC和ELISA检测结果表明,与单纯GT1-7培养组比较,共培养组上清中的Glu浓度显著减少,而GnRH的分泌则明显增加(P<0.05)。结论 GnRH神经元与星形胶质细胞共培养可通过改变GluR(代谢型或离子型)在细胞内的定位与表达,从而增加GnRH的分泌。

Objective To explore the effect of coculture GnRH neuron （GT1-7） with astrocyte on the function of GnRH neuron and the mechanism associated with it.Methods GnRH neurons were cocultured with primary astrocyte for 10 days in the Transwell system.The distribution of GluR in GnRH neuron were detected by immunofluorescence.The expression of GluR in GnRH neuron were tested by Western-blot.The concentration of Glu and GnRH were measured through HPLC and ELISA respectively.Results It was observed that transfer of mGluR5 and GluR1/2/3/4 into nucleus form cytoplasm took place in the coculture group.The expression of mGluR5 and GluR1/2/3/4 in the nucleus were increased.The results of Western-blot coincided with the results of IF.The concentration of Glu in supernatant decreased but the secretion of GnRH increased in the coculture group.Conclusion The coculture of GnRH neuron with astrocyte can benefit the secretion of GnRH via the change of GluR.The distribution and expression of GluR in the GnRH neuron can be changed if GnRH neuron were cocultured with astrocyte.