Na+/K+-pump mutant with a slow charge translocating step

  • J.-D. Horisberger
  • F. Jaisser
  • C. Canessa
  • B. C. Rossier

Abstract

During its transport cycle the Na+/K+-pump transport 3 Na+ ions out of and to K+ ions into the cells. The translocation of the Na+ ions is associated with a net movement of charge across the membrane. Charge translocation by the Na+/K+-pump can be studied as ouabain-sensitive transient current after fast voltage perturbation under Na/Na exchange conditions (5,6). The translocation of charges has been associated with the release of Na+ ions across an external high field access channel (2,7). The structure responsible for Na+ ion translocation is not known.

Keywords

Methionine Ouabain 

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References

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Copyright information

© Dietrich Steinkopff Verlag GmbH & Co. KG, Darmstadt 1994

Authors and Affiliations

  • J.-D. Horisberger
    • 1
  • F. Jaisser
    • 1
  • C. Canessa
    • 1
  • B. C. Rossier
    • 1
  1. 1.Institut de Pharmacologie et de ToxicologieLausanneSwitzerland

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