Role of pH-sensitive ion channels in regulation of cell volume in opossum kidney cells.
Applying the patch-clamp technique to cultured opossum kidney (OK) cells, we investigated effects of pH on the activation of Cl- channels induced by a hyposmotic shock. The Cl- conductance of cell membranes was measured in 145 mM NMG-Cl solution with the whole-cell configuration. Under control conditions, the Cl- conductance was almost negligible. When the cell was exposed to a hyposmotic medium, the Cl- conductance was remarkably elevated. This conductance change was reversibly inhibited by Cl- channel inhibitors, such as DIDS. The activation (pHi) from 7.3 to 7.0, but not influenced by changing the bath pH (pHe). We conclude that the Cl- channel activation by a hyposmotic challenge is highly sensitive to pHi.
Mori
Y
Y
Department of Physiology, Osaka Medical College, Japan.
Kubokawa
M
M
Hagiwara
N
N
Kubota
T
T
Kotera
K
K
Fujimoto
M
M
D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid / Q000494:pharmacology; D000818:Animals; D002118:Calcium; D018118:Chloride Channels / Q000502:physiology*; D006863:Hydrogen-Ion Concentration; D007668:Kidney; D009893:Opossums; D014882:Water-Electrolyte Balance
D018118:Chloride Channels; D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid; D002118:Calcium