[Na, K-ATPase gene expression in hypertrophic and failing hearts]

Na, K-ATPase (Na, K-pump) maintains intracellular ion composition by transporting Na+ and K+ across the cell membrane, and plays an important role in many fundamental cellular and physiological processes such as the control of contractility, excitability, and cell volume regulation. The Na, K-ATPase protein comprises two subunits, a large catalytic alpha subunit and a smaller glycosylated beta subunit. At least three alpha subunit isoforms, alpha 1, alpha 2 and alpha 3, and two beta subunit isoforms, beta 1 and beta 2, have been characterized in rats and humans. The expression of Na, K-ATPase alpha and beta subunits in cardiocytes is directly regulated at a transcriptional level by hormones and ions, such as thyroid hormone and Na+. In the hypertrophic and failing hearts, the expression of cardiac Na, K-ATPase gene is altered, and which might play an important role in the pathogenesis of those disorders.