What is the function of Na,K-ATPase?
Introduction. Na,K-ATPase is an integral membrane protein that mainly functions as an ion pump, hydrolyzing one molecule of ATP to pump three Na+ out of the cell in exchange for two K+ entering the cell per pump cycle.
What is a Na,K-ATPase enzyme?
The sodium–potassium pump (sodium–potassium adenosine triphosphatase, also known as Na⁺/K⁺-ATPase, Na⁺/K⁺ pump, or sodium–potassium ATPase) is an enzyme (an electrogenic transmembrane ATPase) found in the membrane of all animal cells. It performs several functions in cell physiology. Na⁺/K⁺-ATPase pump.
What activates the Na +/ K +/ ATPase pump?
Na+/K+-pump and astrocytes Activation of Na+/K+-ATPase is mediated by Ca2+ partly through Na+ influx via a Na+/Ca2+ exchanger.
What type of transport is Na,K-ATPase?
The sodium-potassium pump carries out a form of active transport—that is, its pumping of ions against their gradients requires the addition of energy from an outside source.
What type of enzyme is ATPase?
ATPases are a group of enzymes that catalyze the hydrolysis of a phosphate bond in adenosine triphosphate (ATP) to form adenosine diphosphate (ADP). They harness the energy released from the breakdown of the phosphate bond and utilize it to perform other cellular reactions.
What is the role of Na+/K+-ATPase in reabsorption in kidneys?
Located on the basolateral aspect of tubule cells, renal Na-K-ATPase plays a key role in the active translocation of Na and K across this membrane as well as in the “secondary active” transport of a number of other solutes.
What is the importance of the Na,K-ATPase in physiology and what physiological role does the beta unit play?
Na,K-ATPase, the Na+ pump, is a transmembrane protein belonging to the P-type ATPase family. Its primary physiological role is the maintenance of large gradients, inward for sodium (Na+) and outward for potassium (K+), across the plasma membrane of all animal cells.
What affects Na K ATPase activity?
Renal Na+,K+-ATPase activity is bidirectionally regulated by natriuretic and antinatriuretic hormones, and a shift in the balance between these forces may lead to salt retention and hypertension. Dopamine plays a key role in this interactive regulation.
What happens when the Na+/K+-ATPase pump is inhibited?
Since Na,K-ATPase is important for maintaining various cellular functions, its inhibition could result in diverse pathologic states. Inhibition of Na,K-ATPase causes high intracellular Na+ ion levels and subsequent increases in intracellular Ca2+ ion through the Na+/Ca2+ exchanger .
Which ion activates ATPase?
The ATPase enzyme causes the hydrolysis of one molecule of ATP and produces the necessary energy to expel three Na+ ions, while allowing two K+ ions to enter.
Where is ATPase produced?
ATPase Structure Most of the ATP is produced in the mitochondria, which comprises of an outer and inner membrane.
What is hydrogen potassium ATPase pump?
The H+-K+-ATPases are ion pumps that use the energy of ATP hydrolysis to transport protons (H+) in exchange for potassium ions (K+). These enzymes consist of a catalytic α-subunit and a regulatory β-subunit.
How does Na +/K +-ATPase work?
The Na + /K + -ATPase extrudes Na + that entered during depolarization and restores the K + lost during repolarization. Once the resting potential is stabilized, Na + channels return to their resting state and are ready for the next depolarization.
Where is Nana +/K +-ATPase expressed in the kidneys?
Na + /K + -ATPase is expressed abundantly in the kidneys . Expression is highest in the thick ascending limb of the loop of Henle (TAL) and the distal convoluted tubule, intermediate in the proximal tubule, relatively low in the collecting ducts and extremely low in the thin limb of loop of Henle.
How does glycoside toxin affect the Na+/K+-ATPase?
The glycoside toxin attaches to the α-subunit of the Na+/K+-ATPase pump to inhibit its action. Because this pump exchanges intracellular sodium ions for extracellular potassium ions, inhibition leads to an overall increase in intracellular sodium ions.
What is Nana+/K+-ATPase?
Na+/K+-ATPase is a ubiquitous plasma membrane-bound enzyme that belongs to the P-type ATPase family of isozymes.