31.8k views
1 vote
Which of the following would occur as a result of the inhibition of Na⁺,K⁺-ATPase?

A. Decreased intracellular Na⁺ concentration
B. Increased intracellular K⁺ concentration
C. Increased intracellular Ca²⁺ concentration
D. Increased Na⁺-glucose cotransport
E. Increased Na⁺-Ca²⁺ exchange

1 Answer

3 votes

Final answer:

The inhibition of Na⁺,K⁺-ATPase would lead to increased intracellular Na⁺ and Ca²⁺ concentrations due to decreased activity of the Na⁺-K⁺ pump and Na⁺-Ca²⁺ exchange, respectively, as well as decreased glucose uptake due to less effective Na⁺-glucose cotransport.

Step-by-step explanation:

The inhibition of Na⁺,K⁺-ATPase will result in a decreased expulsion of Na⁺ from the cell and decreased import of K⁺ into the cell. This causes an increase in intracellular Na⁺ concentration and a decrease in intracellular K⁺ concentration. As Na⁺-K⁺ pump is important for maintaining the electrochemical gradient across the cell membrane and for the function of other transport systems, the inhibition would have several effects.

Increased Na⁺ inside the cell can lead to reduced activity of the Na⁺-Ca²⁺ exchange, which often uses the gradient to expel Ca²⁺ from the cell by importing Na⁺. If more Na⁺ is inside the cell, this exchange process is less efficient, and intracellular Ca²⁺ concentration can increase (Option E).

Additionally, since the Na⁺-glucose cotransport system depends on the Na⁺ gradient maintained by the Na⁺,K⁺-ATPase, inhibition of this enzyme would render the cotransporter less effective, resulting in decreased glucose uptake (Option D).

User Mandel
by
8.0k points