Voltage-gated potassium currents in cultured ovine oligodendrocytes

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.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • 4-Aminopyridine
  • Aminopyridines / pharmacology
  • Animals
  • Cell Survival
  • Cells, Cultured
  • Cesium / pharmacology
  • Electrophoresis
  • Kinetics
  • Membrane Potentials
  • Neuroglia / physiology*
  • Oligodendroglia / physiology*
  • Potassium / physiology*
  • Sheep
  • Tetraethylammonium
  • Tetraethylammonium Compounds / pharmacology


  • Aminopyridines
  • Tetraethylammonium Compounds
  • Cesium
  • Tetraethylammonium
  • 4-Aminopyridine
  • Potassium