[Potassium conductivity of the plasma membrane of frog photoreceptor cells].
Potassium channels, uniformly distributed over the cell surface (0.5 channel/micron2) have been found in isolated fragments of plasma membranes of frog photoreceptor cells. Their conductance under symmetrical conditions (0.1 M KCl at both the membrane surfaces) is 72 +/- 6 pS for rods and 88 +/- 8 pS for cones. The channels are reversibly blocked by tetraethylammonium (TEA), Cs+, Rb+ at intra- and extracellular membrane surfaces. Half-inactivation of a channel occurs at concentrations of TEA, Cs+ and Rb+ at the intracellular surface 0.12, 2.2 and 3.9 mM, correspondingly.
D000818:Animals; D001001:Anura; D002462:Cell Membrane / Q000378:metabolism; D002463:Cell Membrane Permeability; D066298:In Vitro Techniques; D007473:Ion Channels / Q000187:drug effects / Q000378:metabolism*; D010786:Photoreceptor Cells / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism*; D012374:Rod Cell Outer Segment / Q000378:metabolism*; D019789:Tetraethylammonium; D013757:Tetraethylammonium Compounds / Q000494:pharmacology
D007473:Ion Channels; D013757:Tetraethylammonium Compounds; D019789:Tetraethylammonium; D011188:Potassium
Kalievaia provodimost' plazmaticheskoĭ membrany fotoretseptornykh kletok liagushki.