|
|
||||||||
AJP - Cell Physiology, Vol 257, Issue 4 C646-C650, Copyright © 1989 by American Physiological Society
ARTICLES |
N. Inomata, T. Ishihara and N. Akaike
Laboratory of Molecular Pharmacology, Suntory Institute for Biomedical Research, Osaka, Japan.
Processes involved in activation of the acetylcholine (ACh) receptor-operated K+ current (IK) were examined in atrial cells isolated from guinea pig using a "concentration-clamp" technique. This approach allows for the intracellular perfusion and the rapid change of external solution (time constant 4 ms) with cell-attached condition under a single-electrode voltage-clamp condition. The ACh-induced IK increased in a sigmoidal fashion with increasing concentrations of ACh. The Ka value estimated from the concentration-response curve was 3 X 10(-7) M, and the Hill coefficient was 1.0. The activation phase was accelerated not only by increasing the concentration of ACh but also by elevating the temperature. Before activation of the current, there was a brief latent period after the application of ACh. The latent period was shortened considerably with the increase in ACh concentration and in temperature, i.e., 267 +/- 20 ms at 18 degrees C, 98 +/- 11 ms at 26 degrees C, and 44 +/- 6 ms at 37 degrees C for 10(-6) M ACh. These results suggest that the latent period of ACh response seems to be the time lag needed for the activation of K+ channels using remote sensor.
This article has been cited by other articles:
![]() |
M. Yamada The Role of Muscarinic K+ Channels in the Negative Chronotropic Effect of a Muscarinic Agonist J. Pharmacol. Exp. Ther., February 1, 2002; 300(2): 681 - 687. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. V. Sanchez-Vives and D. A. McCormick Functional Properties of Perigeniculate Inhibition of Dorsal Lateral Geniculate Nucleus Thalamocortical Neurons In Vitro J. Neurosci., November 15, 1997; 17(22): 8880 - 8893. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. V. Dunwiddie, L. Diao, and W. R. Proctor Adenine Nucleotides Undergo Rapid, Quantitative Conversion to Adenosine in the Extracellular Space in Rat Hippocampus J. Neurosci., October 15, 1997; 17(20): 7673 - 7682. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Ingram, T. J. Wilding, E. W. McCleskey, and J. T. Williams Efficacy and Kinetics of Opioid Action on Acutely Dissociated Neurons Mol. Pharmacol., July 1, 1997; 52(1): 136 - 143. [Abstract] [Full Text] |
||||
![]() |
D. L. Sodickson and B. P. Bean GABAB Receptor-Activated Inwardly Rectifying Potassium Current in Dissociated Hippocampal CA3 Neurons J. Neurosci., October 15, 1996; 16(20): 6374 - 6385. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |