title: Anion and cation channels in the basolateral membrane of rabbit parietal cells.
abstract: Ion channels in the basolateral membrane of rabbit parietal cells in isolated gastric glands were studied by the patch clamp technique. Whole-cell current-clamp recordings showed that the membrane potential (Em) changed systematically as a function of the chloride concentrations of the basolateral bathing solution ([Cl-]0), and of the pipette (intracellular) solution. The relationship between Em and [Cl-]0 was not affected by additions of histamine, dibutyryl-cAMP, 4-acetoamido-4'-isothiocyanostilbene-2,2'-disulfonic acid and diphenylamine-2-carboxylate. The whole-cell Cl- conductance was insensitive to voltage. In cell-attached and cell-free patch membranes, however, single Cl- channel opening events could not be observed. The value of Em depended little on the basolateral K+ concentration, but inward-rectifier K+ currents were observed in the whole-cell configuration, activated by hyperpolarizing pulses and inhibited by extracellular Ba2+. In cell-attached and cell-free patches, openings of single inward-rectifier K+ channels and non-selective cation channels were infrequently recorded. Neither cAMP nor Ca2+ activated these cation channels. The single K+ channel conductance was about 230 pS under the symmetrical high K+ conditions and was inhibited by intracellular tetraethylammonium ions (TEA). The non-selective cation channel had a voltage-independent single conductance of 22 pS and was not inhibited by TEA.
authors: Faculty of Pharmaceutical Sciences, Toyama Medical and Pharmaceutical University, Japan.
authors: H
authors: H
authors: Sakai
authors: Y
authors: Y
authors: Okada
authors: M
authors: M
authors: Morii
authors: N
authors: N
authors: Takeguchi
mesh_terms: D000818:Animals; D000838:Anions / Q000378:metabolism*; D002412:Cations / Q000378:metabolism*; D002712:Chlorides / Q000378:metabolism / Q000494:pharmacology; D004594:Electrophysiology; D007425:Intracellular Membranes / Q000378:metabolism*; D007473:Ion Channels / Q000502:physiology*; D008564:Membrane Potentials / Q000187:drug effects; D010295:Parietal Cells, Gastric / Q000166:cytology / Q000378:metabolism*; D011188:Potassium / Q000494:pharmacology; D015221:Potassium Channels / Q000502:physiology; D011817:Rabbits; D012964:Sodium / Q000494:pharmacology
chemical_list: D000838:Anions; D002412:Cations; D002712:Chlorides; D007473:Ion Channels; D015221:Potassium Channels; D012964:Sodium; D011188:Potassium