Sodium Modulation of Resting Force, Contractile Properties, and Metabolism with Particular Emphasis on Its Role in the Development of Calcium Overload States
The crucial role of extracellular calcium in modulating cardiac muscle function has been recognized for over 100 years (1). The manner in which changes in extracellular calcium result in altered cellular calcium and therefore changes in resting and active force development, however, is still being explored. A study of factors influencing cellular calcium is relevant not only because cellular calcium controls cardiac force development but also because calcium overload is now recognized to be an accompaniment and perhaps contributor to the functional and metabolic derangements which occur during certain pathologic states (2).
KeywordsExtracellular Calcium Cellular Calcium Mitochondrial Calcium Intracellular Sodium High Energy Phosphate
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