Single-channel properties of volume-sensitive Cl- channel in ClC-3-deficient cardiomyocytes.
It is controversial whether the ClC-3 protein, which is one of the voltage-dependent chloride channel ClC family members, is a candidate for the volume-sensitive outwardly rectifying (VSOR) Cl(-) channel per se or its regulator. Here, for the first time, we examined the single-channel properties of the VSOR Cl(-) channel in ventricular myocytes isolated from ClC-3-deficient mice. The single-channel current induced by cell swelling exhibited Cl(-) selectivity, mild outward rectification, and an intermediate unitary conductance (around 38 pS). A Cl(-) channel blocker, 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS), reversibly inhibited the outward current. These single-channel properties were identical with those in ClC-3 expressing wild-type ventricular myocytes. These results indicate that the single-channel activity of the VSOR Cl(-) channel is independent of the expression of ClC-3 proteins in mouse ventricular myocytes.
Wang
Jun
J
Department of Cell Physiology, National Institute for Physiological Sciences, Okazaki 444-8585, Japan.
Xu
Hongtao
H
Morishima
Shigeru
S
Tanabe
Shigeru
S
Jishage
Kouichi
K
Uchida
Shinichi
S
Sasaki
Sei
S
Okada
Yasunobu
Y
Shimizu
Takahiro
T
D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid / Q000494:pharmacology; D000818:Animals; D002469:Cell Separation; D048429:Cell Size; D018118:Chloride Channels / Q000037:antagonists & inhibitors / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D004594:Electrophysiology; D015870:Gene Expression; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D051379:Mice; D018345:Mice, Knockout; D008817:Mice, Mutant Strains; D032383:Myocytes, Cardiac / Q000737:chemistry* / Q000187:drug effects / Q000502:physiology*; D018408:Patch-Clamp Techniques
D018118:Chloride Channels; C115376:ClC-3 channel; D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid