钾离子通道参与多种生命活动，Kv1.3在神经系统，特别在神经干细胞上分布广泛。神经干细胞兼有神经修复和再生功能，有望用于治疗神经损伤和神经退行性疾病，但干细胞定向分化效率较低，其分化机理不明。我们前期研究发现维生素E能调节钙离子通道，促进神经干细胞分化；我们进一步发现其分化过程中加入Kv1.3阻断剂，能获得更多更成熟的GABA阳性神经元，由此我们推测:阻断Kv1.3引起突触前神经递质GABA释放增多,使突触后神经前体细胞钙离子内流增加, 从而促进其向神经元方向分化。本项目在前期实验基础上,以研究离子通道Kv1.3功能与GABA信号的关系为主线,构建神经干细胞体外分化体系,利用分子生物学、膜片钳技术和RNA干扰等实验手段,探索Kv1.3与GABA信号系统在神经干细胞分化过程中的功能联系。本项目的研究为深入理解神经干细胞的分化机理提供新的理论,为获取更多的成熟神经元及其临床应用提供新的方法。

Potassium ion channels participate multiple biologic activities. Kv1.3 potassium channel is widely expressed on neural system, especially on neural stem cells (NSCs). NSCs are an important and unlimited donor source for cell replacement therapy in the treatment of many neurological diseases, but its differentiation efficiency is low and the mechanism is unclear. Our previous research study revealed that the efficiency of neural differentiation from neural stem cells was enhanced by Vitamin E isomer ∂-tocopherol via Ca2+ channels. Moreover, we found that Kv1.3 blockers induced a significant increase in the proportion of GABA-positive cells. Therefore, we hypothesis that Kv1.3 blockade enhances presynaptic neurotransmitter release, induces postsynaptic membrane depolarization and GABA receptor activation, and then increases excitatory postsynaptic currents (EPSCs) efficiency and intracellular Ca2+ concentration， which can promotes neuronal differentiation. In this project, we explore the effects of Kv1.3 channel on NSC neuronal differentiation and the functional relationship between Kv1.3 and GABA signaling using molecular and cell biology、immunocytochemistry and electrophysiology approaches. It will be beneficial for understanding the mechanism of neural stem cell differentiation, and may provide a new method to obtain more mature and functional neurons from neural stem cells for clinical application.