¹ From the Laboratory of Neurophysiology, Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, and the Marine Biological Laboratory, Woods Hole, Massachusetts.

Dr. Nakajima's present address is the Department of Physiology, School of Medicine, Juntendo University, Hongo, Tokyo, Japan

Under the voltage clamp condition, the K inactivation was analyzed in cells bathed in the isosmotic KCl Lophius-Ringer solution. After conditioning hyperpolarization, the cells respond to depolarizations with increased K permeability, which in turn is decreased during maintained depolarizations. The steady-state levels of the K inactivation as a function of the membrane potential are related by an S-shaped curve similar to that which describes the steady-state Na inactivation in the squid giant axon. TEA reduced the K conductance by a factor which is independent of the potential, and without a shift of the inactivation curve along the voltage axis. The rapid phase of the K activation is less susceptible to TEA than the slow phase of the K activation. Hyperpolarizing steps remove the K inactivation, the rate of the removal being faster the larger the hyperpolarization from the standard potential of about -60 mv.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				X.-T. Hu, S. Basu, and F. J. White Repeated Cocaine Administration Suppresses HVA-Ca2+ Potentials and Enhances Activity of K+ Channels in Rat Nucleus Accumbens Neurons J Neurophysiol, September 1, 2004; 92(3): 1597 - 1607. [Abstract] [Full Text] [PDF]

Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents