Ion Channels and Ion Pumps pp 226-240 | Cite as
Hormonal Modulation of Sodium Pump Activity: Identification of Second Messengers
Abstract
The sodium pump actively transports ions of sodium and potassium across the plasma membrane of most animal cells using energy acquired from the hydrolysis of ATP. Electrochemical gradients of sodium and potassium are formed that initiate the subsequent diffusion of sodium and potassium, which helps establish the resting membrane potential. Under normal physiologic conditions three Na+ ions are expelled in exchange for two K+ ions, which produces a net charge movement that also contributes to the resting membrane potential. The sodium pump regulates cell volume and the sodium gradient itself subserves the secondary transport of other amino acids, sugars, calcium ions, and protons. In more general terms the sodium pump is the major mechanism responsible for the ability of the body to regulate levels of sodium and potassium. The energy spent in this capacity is a major source of heat production.
Keywords
ATPase Activity Adenosine Triphosphatase Sodium Pump Intracellular Sodium Ouabain BindingPreview
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References
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