Mammalian optic nerve fibers display two pharmacologically distinct potassium channels.

Abstract

A suction electrode recording technique was used to study action potential characteristics of rat optic nerve fibers. Two pharmacologically distinct potassium channels are described. One is sensitive to 4-aminopyridine (4-AP) and the other to tetraethylammonium (TEA). 4-AP application leads to a substantial broadening of the optic nerve action potential, but TEA does not. 4-AP application also elicits a TEA-sensitive post-spike positivity, i.e. an intracellular hyperpolarization. From these results we suggest that the 4-AP-sensitive channel, not the TEA-sensitive channel, is primarily responsible for action potential repolarization of mammalian optic nerve fibers.

Cite this paper

@article{Kocsis1986MammalianON, title={Mammalian optic nerve fibers display two pharmacologically distinct potassium channels.}, author={Jeffery D. Kocsis and Terry Gordon and Stephen G. Waxman}, journal={Brain research}, year={1986}, volume={383 1-2}, pages={357-61} }