Jelitai M, Anderová M, Chvátal A, Madarász E
Laboratory of Neural Cell and Developmental Biology, Institute of Experimental Medicine of the Hungarian Academy of Sciences, Budapest, Hungary.
J Neurosci Res. 2007 Jun;85(8):1606-17. doi: 10.1002/jnr.21282.
Despite the accumulating data on the molecular and cell biological characteristics of neural stem/progenitor cells, their electrophysiological properties are not well understood. In the present work, changes in the membrane properties and current profiles were investigated in the course of in vitro-induced neuron formation in NE-4C cells. Induction by retinoic acid resulted in neuronal differentiation of about 50% of cells. Voltage-dependent Na+ currents appeared early in neuronal commitment, often preceding any morphological changes. A-type K+ currents were detected only at the stage of network formation by neuronal processes. Flat, epithelial- like, nestin-expressing progenitors persisted beside differentiated neurons and astrocytes. Stem/progenitor cells were gap junction coupled and displayed large, symmetrical, voltage-independent currents. By the blocking of gap junction communication, voltage-independent conductance was significantly reduced, and delayed-rectifying K+ currents became detectable. Our data indicate that voltage-independent symmetrical currents and gap junction coupling are characteristic physiological features of neural stem and progenitor cells regardless of the developmental state of their cellular environment.
尽管关于神经干/祖细胞的分子和细胞生物学特性已有越来越多的数据，但对其电生理特性的了解仍不充分。在本研究中，我们研究了NE-4C细胞在体外诱导神经元形成过程中膜特性和电流分布的变化。视黄酸诱导导致约50%的细胞发生神经元分化。电压依赖性Na+电流在神经元定向分化早期出现，通常先于任何形态学变化。仅在神经元突起形成网络阶段检测到A型K+电流。扁平的、上皮样的、表达巢蛋白的祖细胞在分化的神经元和星形胶质细胞旁持续存在。干/祖细胞通过缝隙连接耦合，并表现出大的、对称的、电压非依赖性电流。通过阻断缝隙连接通讯，电压非依赖性电导显著降低，延迟整流K+电流变得可检测到。我们的数据表明，电压非依赖性对称电流和缝隙连接耦合是神经干细胞和祖细胞的特征性生理特性，与它们细胞环境的发育状态无关。
