Chloride channels in primary cultures of seawater fish (Dicentrarchus labrax) gill.
Patch-clamp experiments were undertaken on primary cultures of respiratory cells originating from sea bass (Dicentrarchus labrax) gills. A small-conductance Cl- channel of 8 pS was characterized in cell-attached configuration with 140 mM N-methyl-D-glucamine-Cl in the pipette and bath solutions. No activity was recorded below a membrane holding potential of +20 mV (-Vp, referenced to the pipette solution), and the channel showed an inward rectification. In the inside-out configuration the Cl- channel was active at all membrane holding potentials. Its open probability strongly increased with membrane depolarization. The channel activity could be increased by the application of protein kinase A+ATP. This channel was inhibited by 5-nitro-2-(3-phenylpropylamino)-benzoic acid, diphenylamino-2-carboxylic acid, and I- and was insensitive to 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid. The presence of Cl- channels in the apical membrane of respiratory cells provides additional evidence for an important role of this cell type in the control of ion homeostasis of seawater fish.
Duranton
C
C
Unité Mixte de Recherche Centre National de la Recherche Scientifique 6548, Université de Nice-Sophia Antipolis, France.
Tauc
M
M
Avella
M
M
Poujeol
P
P
D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid / Q000494:pharmacology; D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D001492:Bass; D002478:Cells, Cultured; D018118:Chloride Channels / Q000037:antagonists & inhibitors / Q000502:physiology*; D017868:Cyclic AMP-Dependent Protein Kinases / Q000494:pharmacology; D005880:Gills / Q000166:cytology / Q000502:physiology*; D015640:Ion Channel Gating; D008536:Meglumine / Q000494:pharmacology; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D008954:Models, Biological; D009579:Nitrobenzoates / Q000494:pharmacology; D018408:Patch-Clamp Techniques; D011336:Probability; D012623:Seawater; D012974:Sodium Iodide / Q000494:pharmacology; D062367:ortho-Aminobenzoates / Q000494:pharmacology
D018118:Chloride Channels; D009579:Nitrobenzoates; D062367:ortho-Aminobenzoates; C058176:5-nitro-2-(3-phenylpropylamino)benzoic acid; D008536:Meglumine; D000255:Adenosine Triphosphate; C001209:fenamic acid; D017868:Cyclic AMP-Dependent Protein Kinases; D012974:Sodium Iodide; D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid