| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Departments of 1 Autonomic Physiology and 2 Cardiovascular Diseases, Medical Research Institute, Tokyo Medical and Dental University, Chiyoda-ku, Tokyo 101, Japan
In the
Xenopus oocyte heterologous expression
system, the electrophysiological characteristics of rabbit ClC-2
current and its contribution to volume regulation were examined.
Expressed currents on oocytes were recorded with a two-electrode
voltage-clamp technique. Oocyte volume was assessed by taking pictures
of oocytes with a magnification of ×40. Rabbit ClC-2 currents
exhibited inward rectification and had a halide anion permeability
sequence of Cl
Br 
I F. ClC-2 currents were
inhibited by 5-nitro-2-(3-phenylpropylamino)benzoic acid (NPPB),
diphenylamine-2-carboxylic acid (DPC), and anthracene-9-carboxylic acid
(9-AC), with a potency order of NPPB > DPC = 9-AC, but were resistant to stilbene disulfonates. These characteristics are similar
to those of rat ClC-2, suggesting rabbit ClC-2 as a counterpart of rat
ClC-2. During a 30-min perfusion with hyposmolar solution, current
amplitude at 
160 mV and oocyte diameter were compared among
three groups: oocytes injected with distilled water, oocytes injected
with ClC-2 cRNA, and oocytes injected with ClC-2
NT cRNA (an open
channel mutant with NH2-terminal
truncation). Maximum inward current was largest in ClC-2NT-injected
oocytes (5.9 ± 0.4 µA), followed by ClC-2-injected oocytes
(4.3 ± 0.6 µA), and smallest in water-injected oocytes
(0.2 ± 0.2 µA), whereas the order of increase in oocyte
diameter was as follows: water-injected oocytes (9.0 ± 0.2%) > ClC-2-injected oocytes (5.3 ± 0.5%) > ClC-2NT-injected oocytes (1.1 ± 0.2%). The findings that oocyte swelling was
smallest in oocytes with the largest expressed currents suggest that
ClC-2 currents expressed in Xenopus
oocytes appear to act for volume regulation when exposed to a
hyposmolar environment.
chloride channel; voltage clamp; cell swelling; ClC supergene family
This article has been cited by other articles:
|
|
 |
|
  H. F. Bao, L. Liu, J. Self, B. J. Duke, R. Ueno, and D. C. Eaton A synthetic prostone activates apical chloride channels in A6 epithelial cells Am J Physiol Gastrointest Liver Physiol, August 1, 2008; 295(2): G234 - G251. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W.-Z. Lan, H. Abbas, H. D. Lam, A.-M. Lemay, and C. E. Hill Contribution of a time-dependent and hyperpolarization-activated chloride conductance to currents of resting and hypotonically shocked rat hepatocytes Am J Physiol Gastrointest Liver Physiol, February 1, 2005; 288(2): G221 - G229. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Catalan, I. Cornejo, C. D. Figueroa, M. I. Niemeyer, F. V. Sepulveda, and L. P. Cid ClC-2 in guinea pig colon: mRNA, immunolabeling, and functional evidence for surface epithelium localization Am J Physiol Gastrointest Liver Physiol, October 1, 2002; 283(4): G1004 - G1013. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. J. Jentsch, V. Stein, F. Weinreich, and A. A. Zdebik Molecular Structure and Physiological Function of Chloride Channels Physiol Rev, April 1, 2002; 82(2): 503 - 568. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. X. Weng, L. Mo, H. L. Hellmich, A. S. L. Yu, T. Wood, and N. K. Wills Expression and regulation of ClC-5 chloride channels: effects of antisense and oxidants Am J Physiol Cell Physiol, June 1, 2001; 280(6): C1511 - C1520. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Bali, J. Lipecka, A. Edelman, and J. Fritsch Regulation of ClC-2 chloride channels in T84 cells by TGF-{alpha} Am J Physiol Cell Physiol, June 1, 2001; 280(6): C1588 - C1598. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Fahlke Ion permeation and selectivity in ClC-type chloride channels Am J Physiol Renal Physiol, May 1, 2001; 280(5): F748 - F757. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. M. Roman, R. L. Smith, A. P. Feranchak, G. H. Clayton, R. B. Doctor, and J. G. Fitz ClC-2 chloride channels contribute to HTC cell volume homeostasis Am J Physiol Gastrointest Liver Physiol, March 1, 2001; 280(3): G344 - G353. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 F. C. Britton, W. J. Hatton, C. F. Rossow, D. Duan, J. R. Hume, and B. Horowitz Molecular distribution of volume-regulated chloride channels (ClC-2 and ClC-3) in cardiac tissues Am J Physiol Heart Circ Physiol, November 1, 2000; 279(5): H2225 - H2233. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. P. Tewari, D. H. Malinowska, A. M. Sherry, and J. Cuppoletti PKA and arachidonic acid activation of human recombinant ClC-2 chloride channels Am J Physiol Cell Physiol, July 1, 2000; 279(1): C40 - C50. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. J. Blaisdell, R. D. Edmonds, X.-T. Wang, S. Guggino, and P. L. Zeitlin pH-regulated chloride secretion in fetal lung epithelia Am J Physiol Lung Cell Mol Physiol, June 1, 2000; 278(6): L1248 - L1255. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. Duan, L. Ye, F. Britton, B. Horowitz, and J. R. Hume A Novel Anionic Inward Rectifier in Native Cardiac Myocytes Circ. Res., March 3, 2000; 86 (4): e63 - e71. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Stroffekova, E. Y. Kupert, D. H. Malinowska, and J. Cuppoletti Identification of the pH sensor and activation by chemical modification of the ClC-2G Cl- channel Am J Physiol Cell Physiol, October 1, 1998; 275(4): C1113 - C1123. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Hiraoka, S. Kawano, Y. Hirano, and T. Furukawa Role of cardiac chloride currents in changes in action potential characteristics and arrhythmias Cardiovasc Res, October 1, 1998; 40(1): 23 - 33. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Nakajima, T. Furukawa, T. Tanaka, Y. Katayama, R. Nagai, Y. Nakamura, and M. Hiraoka Novel Mechanism of HERG Current Suppression in LQT2 : Shift in Voltage Dependence of HERG Inactivation Circ. Res., August 24, 1998; 83(4): 415 - 422. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
