Abstract
The primary role of the Na-K pump is the generation and maintenance of transmembrane Na+ and K+ gradients. The Na-K pump actively transports these ions across the cell membrane against concentration gradients. Although there are other mechanisms and ion channels that modify intracellular Na+ and K+ concentrations, the Na-K pump is essential for maintaining an intracellular environment of low Na+ and high K+ concentrations. The K+ and Na+ gradients in turn are the basis for transmembrane potentials, membrane excitability, and action potentials in the cardiac muscle. In addition, activity of the Na-K pump indirectly modulate intracellular Ca2+ concentrations through the Na/Ca exchanger. A low intracellular Ca2+ concentration is necessary for relaxation of heart muscle, proper functions of mitochondria, and Na-K pump activity. Equally important is the function of Na+, K+-ATPase as the only known receptor for cardiac glycosides.
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© 1996 Springer Science+Business Media Dordrecht
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Ng, YC., Akera, T. (1996). Na-K pump: Multiple isoforms and their roles in cardiac functions. In: Morad, M., Ebashi, S., Trautwein, W., Kurachi, Y. (eds) Molecular Physiology and Pharmacology of Cardiac Ion Channels and Transporters. Developments in Cardiovascular Medicine, vol 182. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-3990-8_48
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DOI: https://doi.org/10.1007/978-94-011-3990-8_48
Publisher Name: Springer, Dordrecht
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