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Basic Research in Cardiology

, Volume 75, Issue 3, pp 455–459 | Cite as

Vanadate interaction with the Na, K-ATPase an assay of serum vanadate based on the displacement of (48V) vanadate from Na, K-ATPase

  • O. Hansen
Original Contributions

Summary

Under optimum conditions for vanadate binding to Na, K-ATPase equilibrium binding data for a range of vanadate concentrations were compiled. Scatchard plots indicated an identical binding capacity for vanadate and ouabain with conventionally prepared Na, K-ATPase batches. A method for determination of vanadate in serum based upon the high affinity of vanadate for Na, K-ATPase is described. The method takes advantage of the shift in equilibrium binding of (48V) vanadate upon addition of an aliquot of vanadate-containing serum. It is shown that the interplay between vanadate and ouabain in vanadate-facilitated oubain binding to Na, K-ATPase leads to an enzyme-vanadate-ouabain complex to which vanadate is rather firmly bound.

Keywords

Public Health Vanadate Optimum Condition Binding Capacity Ouabain 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Einfluß von Vanadat auf die (Na++K+)-ATPase-Aktivität Eine Vanadat-Nachweismethode, basierend auf der [48V]-Vanadatverdrängung aus der Bindung an die (Na++K+)-ATPase

Zusammenfassung

Die [48V]Vanadatbindung an die (Na++K+)-ATPase wurde unter Äquilibriumbedingungen und bei optimalen Inkubationsbedingungen gemessen. Scatchard-Analysen der Vanadatbindung ergeben eine identische Bindungskapazität für Vanadat und Ouabain (g-Strophanthin) in angereicherten (Na++K+)-ATPase-Präparationen. Mit Hilfe dieser hochaffinen Vanadatbindung an die (Na++K+)-ATPase ist eine Bestimmungsmethode für Vanadat im Serum möglich, die sich das Prinzip des „Radiorezeptor-Assays” zunutze macht. Außerdem wird experimentell nachgewiesen, daß die [3H]Ouabain-Bindung an die (Na++K+)-ATPase in Gegenwart von Vanadat zu einem Enzym-Vanadat-Ouabain-Komplex führt, in dem Vanadat relativ fest gebunden wird.

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References

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    Hansen, O., J. Jensen, J. G. Nørby, P. Ottolenghi: A new proposal regarding the subunit composition of (Na++K+)-ATPase. Nature280, 410–412 (1979).PubMedGoogle Scholar
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    Cantley, L. C. Jr.,L. G. Cantley, L. Josephson. A characterization of vanadate interactions with the (Na, K)-ATPase. Mechanistic and regulatory implications. J. Biol. Chem.253, 7361–7368 (1978).PubMedGoogle Scholar
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    Hansen, O.: Reactive states of the Na, K-ATPase demonstrated by the stability of the enzyme-ouabain complex. In: Na, K-ATPase. Structure and Kinetics, eds.Skou, J. C., J. G. Nørby: p. 169–180 (London 1979).Google Scholar

Copyright information

© Dr. Dietrich Steinkopff Verlag 1980

Authors and Affiliations

  • O. Hansen
    • 1
  1. 1.Fysiologisk InstitutÅrhus UniversitetÅrhus CDenmark

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