Soliven B, Szuchet S, Arnason B G, Nelson D J
Department of Neurology, University of Chicago, Illinois 60637.
J Neurosci. 1988 Jun;8(6):2131-41. doi: 10.1523/JNEUROSCI.08-06-02131.1988.
Cultured oligodendrocytes (OLGs) develop processes and form myelin following attachment to a substratum. We applied the whole-cell voltage-clamp technique to identify and characterize the ionic currents of OLGs in culture. Within 2 d after attachment, OLGs extended processes and began to express an outward current that represents a composite response of an inactivating/transient component and a non-inactivating component. The current had a reversal potential of -66 mV and was sensitive to potassium channel blockers. After 4-5 d in culture, the transient component was less prominent, often accompanied by an increase in noninactivating or steady-state outward current. In addition, there was an increase in inward rectifier current. Four of 7 cells that failed to develop processes exhibited only linear high-resistance membranes. We conclude that cultured OLGs express 3 voltage-gated potassium conductances: (1) a transient outward current, (2) a noninactivating outward current, and (3) an inward rectifier current. The sequential appearance of the several currents may relate, at least in part, to process formation.
培养的少突胶质细胞（OLGs）附着于基质后会形成突起并形成髓鞘。我们应用全细胞电压钳技术来识别和表征培养的OLGs的离子电流。在附着后2天内，OLGs伸出突起，并开始表达一种外向电流，该电流代表失活/瞬态成分和非失活成分的复合反应。该电流的反转电位为-66 mV，对钾通道阻滞剂敏感。培养4-5天后，瞬态成分不那么突出，常伴有非失活或稳态外向电流增加。此外，内向整流电流增加。7个未形成突起的细胞中有4个仅表现出线性高电阻膜。我们得出结论，培养的OLGs表达3种电压门控钾电导：（1）瞬态外向电流，（2）非失活外向电流，（3）内向整流电流。几种电流的顺序出现可能至少部分与突起形成有关。
