... the past three decades, has clearly shown that in addition to its established role as an ion pump, Na+/K+-ATPase also functions as a signal transducer to relay messages from the plasma membrane ... J., Haas, M., Shapiro, J.I., Askari, A & Xie, Z (2000) Ouabain interaction with cardiac Na+ +-ATPase /K initiates signal cascades independent of changes in intracellular Na+ and Ca2+ concentrations ... the past few years [22–26] have clearly indicated that the same nontoxic concentrations of ouabain that cause partial inhibition of Na+/K+-ATPase and an increase in cardiac contractility, also...