title: Effect of ethanol on tracheal potassium channels reconstituted into bilayer lipid membranes.
abstract: We examined the effect of ethanol on single potassium channels derived from plasma membranes of bovine tracheal smooth muscles. The observed potassium channels had a conductance of 296 +/- 31 pS (mean +/- S.D.) in symmetrical 250 mmol/l KCl solutions, and exhibited a voltage- and Ca2+-dependence similar to BKCa channels. Ethanol at 50, 100 and 200 mM concentrations increased the probability of open potassium channels to 112 +/- 5, 127 +/- 7 and 121 +/- 13% (mean +/- S.E.M.), respectively. It is suggested that increased activity of the BKCa channels by ethanol hyperpolarizes the plasma membrane and thus may contribute to relaxation of tracheal smooth muscle.
authors.affiliation: Institute of Molecular Physiology and Genetics, Slovak Academy of Sciences, Bratislava.
authors.forename: V
authors.initials: V
authors.lastname: Kominková
authors.forename: M
authors.initials: M
authors.lastname: Magova
authors.forename: A
authors.initials: A
authors.lastname: Mojzisová
authors.forename: E
authors.initials: E
authors.lastname: Maleková
authors.forename: K
authors.initials: K
authors.lastname: Ondrias
mesh_terms: D000818:Animals; D002118:Calcium / Q000494:pharmacology; D002417:Cattle; D002462:Cell Membrane / Q000737:chemistry / Q000502:physiology; D004553:Electric Conductivity; D000431:Ethanol / Q000494:pharmacology*; D015640:Ion Channel Gating / Q000187:drug effects; D008051:Lipid Bilayers / Q000378:metabolism*; D015221:Potassium Channels / Q000187:drug effects* / Q000502:physiology*; D011189:Potassium Chloride / Q000494:pharmacology; D014132:Trachea / Q000737:chemistry* / Q000502:physiology
chemical_list: D008051:Lipid Bilayers; D015221:Potassium Channels; D000431:Ethanol; D011189:Potassium Chloride; D002118:Calcium