The presence of voltage-gated sodium, potassium and chloride channels in rat cultured astrocytes - PubMed (original) (raw)

The presence of voltage-gated sodium, potassium and chloride channels in rat cultured astrocytes

S Bevan et al. Proc R Soc Lond B Biol Sci. 1985.

Abstract

Patch-clamp recording from the plasmalemma of rat cultured astrocytes reveals the presence of both voltage-dependent sodium and voltage-dependent potassium conductances. These conductances are similar but not identical to the corresponding conductances in the axolemma. Whereas the h infinity relation of the sodium channels has the same voltage dependence as in the nodal axolemma, the peak current-voltage relation is shifted by about 30 mV along the voltage axis in the depolarizing direction. It is speculated that the glial cells synthesize sodium and potassium channels for later insertion into the axolemma of neighbouring axons. The astrocytes also express a plasmalemmal voltage-dependent anion conductance that is turned on at about -40 mV (that is, near the resting potential of the cultured astrocytes). The channels involved are large enough to be just permeable to glutamate but not to ascorbate. It is suggested that the conductance of this channel for chloride plays a physiological role in the spatial buffering of potassium by glial cells.

PubMed Disclaimer

Similar articles

Cited by

Publication types

MeSH terms

Substances

LinkOut - more resources