These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Stimulation of monovalent cation fluxes by electron donors in the human red cell membrane.
    Author: Garcia-Sancho J, Sanchez A, Herreros B.
    Journal: Biochim Biophys Acta; 1979 Sep 04; 556(1):118-30. PubMed ID: 476114.
    Abstract:
    When human red cells are incubated at 37 degrees C with the artificial electron donor system ascorbate + phenazine methosulphate the fluxes of Rb+ (K+) through the cell membrane are increased. The effect of this donor system is much stronger in energy-depleted than in normal cells. The same effects are produced by HS-glutathione, NADH or NADPH loaded into resealed ghosts, but these electron donors were ineffective when added to the incubation medium. The Rb+ (K+) fluxes induced by electron donors resemble closely those induced by an increase of intracellular Ca2+ (Gardos effect). The electron donors require the presence of intracellular Ca2+ to be effective, but at levels that do not stimulate by themselves the fluxes of K+. Flavoenzyme inhibitors (atebrin and chlorpromazine), oligomycin and quinine prevented the effects of both electron donors and Ca2+ alone; antimycin, upcouplers and ethacrynic acid inhibited them partially; ouabain, furosemide, and rotenone had no effect. The results could be explained if the effect of electron donors is to bring about a change in the redox state of some membrane component(s) that makes intracellular Ca2+ more effective to elicit rapid K+ movements. Plasma membrane oxidoreductase activities could be engaged in this change.
    [Abstract] [Full Text] [Related] [New Search]