|
|
||||||||
AJP - Cell Physiology, Vol 265, Issue 2 C328-C336, Copyright © 1993 by American Physiological Society
ARTICLES |
A. Takahashi, H. Yamaguchi and H. Miyamoto
Department of Physiology, School of Medicine, University of Tokushima, Japan.
The K+ channel of HeLa S3 cells in metaphase was analyzed by inside-out and whole cell patch-clamp techniques. The channel had the characteristics of strong inward rectification, small conductance (22 pS at -100 mV), and dependence on intracellular Ca2+. We investigated the cell cycle dependency of the channel, using cells synchronized by harvesting them at the mitotic stage. The cell capacitance increased gradually with increases in the cell volume toward the S phase. The inward K+ currents through the channel at fixed membrane potentials were highest in early G1 and then decreased with time to a minimum in the S phase, increasing again in the M phase. The permeabilities at fixed membrane potentials were also highest in early G1, decreased to minima in the S phase, and increased again toward the next mitosis. In contrast, mean amplitude and the open probability of the single channel at a fixed membrane potential (-60 mV) did not change significantly during the cell cycle. Therefore the capacitance increases with progression of the cell cycle, whereas the permeability decreases from early G1 to an apparent minimum in the S phase. These changes may be caused by cell cycle-dependent changes in the number of channels.
This article has been cited by other articles:
![]() |
E. K. Hoffmann, I. H. Lambert, and S. F. Pedersen Physiology of Cell Volume Regulation in Vertebrates Physiol Rev, January 1, 2009; 89(1): 193 - 277. [Abstract] [Full Text] [PDF] |
||||
![]() |
C.-C. Shieh, M. Coghlan, J. P. Sullivan, and M. Gopalakrishnan Potassium Channels: Molecular Defects, Diseases, and Therapeutic Opportunities Pharmacol. Rev., December 1, 2000; 52(4): 557 - 594. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. LANG, G. L. BUSCH, M. RITTER, H. VOLKL, S. WALDEGGER, E. GULBINS, and D. HAUSSINGER Functional Significance of Cell Volume Regulatory Mechanisms Physiol Rev, January 1, 1998; 78(1): 247 - 306. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Kuga, S. Kobayashi, Y. Hirakawa, H. Kanaide, and A. Takeshita Cell Cycle-Dependent Expression of L- and T-Type Ca2+ Currents in Rat Aortic Smooth Muscle Cells in Primary Culture Circ. Res., July 1, 1996; 79(1): 14 - 19. [Abstract] [Full Text] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |