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Scaling Of Na+, K+-Atpase Molecular Activity And Membrane Fatty Acid Composition In Mammalian And Avian Hearts, Anthony J. Hulbert, Paul Else, Kurt Haga, Nigel Turner

Faculty of Health and Behavioural Sciences - Papers (Archive)

We have examined Na⁺,K⁺‐ATPase molecular activity and membrane fatty acid composition in the heart of six mammalian and eight avian species ranging in size from 30 g in mice to 280 kg in cattle and 13 g in zebra finches to 35 kg in emus, respectively. Na⁺,K⁺‐ATPase activity scaled negatively with body mass in both mammals and birds. In small mammals, the elevated enzyme activity was related to allometric changes in both the concentration and molecular activity (turnover rate) of Na⁺,K⁺‐ATPase enzymes, while in small birds, higher Na …