大鼠脑内小胶质细胞神经营养素受体的表达

EXPRESSION OF NEUROTROPHIC RECEPTORS IN RAT BRAIN MICROGLIA

神经营养素在神经元的生长、发育中的重要作用已有许多报道,但对神经胶质细胞的作用及其作用机制却知之甚少。在本研究中,我们着重对体外培养的小胶质细胞所表达的神经营养素受体进行了分析。首先,利用酚-氯仿法提取了总的细胞RNA,然后通过特异引物采用反转录多聚酶链式反应(RT-PCR)扩增得到cDNA,再用琼脂糖凝胶电泳、DNA印迹法和免疫细胞化学染色法对神经营养素受体(Trks)进行了测定。实验结果表明:体外培养的大鼠脑小胶质细胞表达高亲和力神经营养素受体TrkA、TrkB和TrkC,以及低亲和力NGF受体LNGFRp75。因此推断,神经营养素对小胶质细胞的生理及调节作用可能是通过它们相应的受体(Trks和LNGFRp75)介导的。这些结果为进一步研究神经营养素在神经系统中的作用机制及小胶质细胞的生理功能提供了资料。

It has been extensively investigated that neurotrophins play an important role in neuronal development and sur-vival, but the mechanism keep unclcar. In present study, we detected the expression of neurotrophin receptors (Tr-kA, TrkB, TrkC and LNGFRp75)by RT-PCR, southern blot and immunocytochemical staining. The results revealed that cultured rat microglia express high-affinity receptors TrkA, TrkB and TrkC, and low-affinity receptor LNGFRp75 both in mRNA and protein Ievel. Thus, these results appear to indicate that the neurotrophin family has a regulative role in the function of microglia through trk-mediated signal transduction.