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PubMed · 8520533

Decrease in the ratio of high- to low-affinity isozymes of (Na+ +K+)-ATPase during the development of rat cardiac ventricles.

C M Alves·C L Silva·G M Moura·F Noël
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Abstract

The ratio of (Na+ +K+)-ATPase (EC 3.6.1.3.)isoforms with high and low affinity for cardiac glycosides was studied in heart preparations from neonatal, 3-month and 6-month old Wistar rats. Biphasic ouabain inhibition curves of (Na+ +K+)-ATPase activity indicated that the relative contribution of the high-affinity process decreased from 34% at 9 days to 23% at 3 months and to 10% at 6 months. Scatchard plots for [3H]ouabain binding were curvilinear and indicated that the relative contribution of the high-affinity sites (Kd = 0.1-0.25 microM) decreased by about one-half between 3 months (19-24%, N = 2) and 6 months (9-11%, N = 2).

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Age FactorsAnimalsBinding SitesHeart VentriclesIsoenzymesRatsRats, WistarSodium-Potassium-Exchanging ATPaseComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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C M Alves, C L Silva, G M Moura, F Noël. 1995. Decrease in the ratio of high- to low-affinity isozymes of (Na+ +K+)-ATPase during the development of rat cardiac ventricles.. https://pubmed.ncbi.nlm.nih.gov/8520533/

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