Summary
It was assumed that Na,K-ATPase from grey matter of ox brain contains two independent populations of ouabain receptors and that the high affinity component is sensitive to pyrithiamin whereas the low affinity component resists treatment with the vitamin analogue. With these assumptions the two components of digitalis receptors and their affinities (the reciprocal of the slope) are calculated. The curves drawn from the calculated components and dissociation constants are seen to fit the experimental points well.
Ouahain binding data obtained before and after treatment of Na,K-ATPase from ox brain with pyrithiamin are thus compatible with a model assuming two independent populations of receptors (and thus enzymes) in this preparation.
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References
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© 1986 Springer-Verlag Berlin Heidelberg
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Hansen, O. (1986). Isoenzymes of Na,K-ATPase identified by pyrithiamin. In: Erdmann, E., Greef, K., Skou, J.C. (eds) Cardiac Glycosides 1785–1985. Steinkopff, Heidelberg. https://doi.org/10.1007/978-3-662-11292-2_6
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DOI: https://doi.org/10.1007/978-3-662-11292-2_6
Publisher Name: Steinkopff, Heidelberg
Print ISBN: 978-3-662-11294-6
Online ISBN: 978-3-662-11292-2
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