Membrane potentials associated with Ca-induced K conductance in human red blood cells: studies with a fluorescent oxonol dye, WW 781

The Journal of Membrane Biology
J C Freedman, T S Novak

Abstract

A divalent anionic dye, bis-[3-methyl-1-p-sulfophenyl-5-pyrazolone-(4)]-pentamethine oxonol (WW 781) is a rapidly responding fluorescent indicator of KCl diffusion potentials induced in human red blood cells with valinomycin, gramicidin, and with the Ca ionophore A 23187 in the presence of external Ca. WW 781 has a sensitivity of 0.13% delta F/mV, a detection limit of 10 mV, a response time of less than 1 sec, and exhibits a decrease in fluorescence intensity upon hyperpolarization without detectable shifts in absorption or emission peaks. This dye does not perturb the normal resting potential, and unlike the slow permeant cyanine dyes, does not inhibit Ca-induced K conductance in human red blood cells. However, WW 781 does stimulate Ca-induced unidirectional Rb efflux. With Ca plus A 23187, the initial rapid change in dye fluorescence is sensitive to [Ca]o and to [A 23187], is reversible with excess EGTA, and is inhibited by quinine, oligomycin, and by trifluoperazine. A biphasic dependence of hyperpolarization on Ko is evident at pH 6, where the ionic selectivity of activation is K, Rb greater than Cs greater than Na and that of conductance is K, Rb greater than Cs. Conditions were defined which permitted continuous monitorin...Continue Reading

References

Dec 4, 1975·The Journal of Membrane Biology·P A KnaufH Passow
Feb 17, 1976·The Journal of Membrane Biology·U V LassenB Vestergaard-Bogind
Mar 1, 1977·The Journal of General Physiology·P A KnaufA Rothstein
Sep 22, 1978·Biochimica Et Biophysica Acta·R I MaceyF W Orme
Jan 1, 1977·Advances in Experimental Medicine and Biology·J F Hoffman, R M Blum
Jan 1, 1978·Reviews of Physiology, Biochemistry and Pharmacology·L B Cohen, B M Salzberg
Jan 1, 1979·Annual Review of Biophysics and Bioengineering·A S Waggoner
Jun 1, 1979·The Journal of General Physiology·J O Wieth, M T Tosteson
Aug 1, 1979·The Journal of General Physiology·J C Freedman, J F Hoffman
Mar 1, 1976·The Journal of Physiology·T J Simons
Mar 1, 1976·The Journal of Physiology·T J Simons
Mar 1, 1969·Acta Physiologica Scandinavica·A EkmanS Salminen
Dec 3, 1971·Biochimica Et Biophysica Acta·J R Riordan, H Passow
Feb 16, 1972·Biochemical and Biophysical Research Communications·R M Blum, J F Hoffman
Aug 9, 1972·Biochimica Et Biophysica Acta·V B Myers, D A Haydon
Oct 1, 1972·The Journal of General Physiology·F M Kregenow, J F Hoffman
Jan 1, 1980·Annals of the New York Academy of Sciences·J O WiethJ Funder
Mar 15, 1981·The Journal of Membrane Biology·E Reichstein, A Rothstein
Feb 15, 1981·The Journal of Membrane Biology·R K GuptaC H Wang
Jan 1, 1981·The Journal of Membrane Biology·T J BeelerA N Martonosi
Jan 1, 1981·The Journal of Membrane Biology·R Rosenberg
May 4, 1962·Biochemical and Biophysical Research Communications·P G HEYTLER, W W PRICHARD
Jan 1, 1963·Archives of Biochemistry and Biophysics·J T DODGED J HANAHAN
Jan 16, 1960·Nature·J F HOFFMANR WHITTAM
Dec 1, 1971·The Journal of Membrane Biology·R M Blum, J F Hoffman

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Citations

Jan 1, 1984·The Journal of Membrane Biology·E M BifanoJ C Freedman
Jan 1, 1983·The Journal of Membrane Biology·J C Freedman
Aug 1, 1988·The Journal of Membrane Biology·E B GeorgeA S Waggoner
Apr 1, 1996·Journal of Photochemistry and Photobiology. B, Biology·J Plásek, K Sigler
Mar 1, 1990·Proceedings of the National Academy of Sciences of the United States of America·A Heinz, J F Hoffman
Aug 1, 1993·The American Journal of Physiology·N M RahaP A Knauf
Feb 1, 1987·The American Journal of Physiology·L M CrespoJ C Freedman
Oct 1, 1995·The American Journal of Physiology·P A KnaufK Hahn
Mar 15, 1990·Biochimica Et Biophysica Acta·J C Smith
Apr 30, 1992·Biochemical and Biophysical Research Communications·L WittenkellerR Ramasamy

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