Outline the Steps in the Mechanism of Action of Digoxin

Outline the steps in the mechanism of action of digoxin.

A) Digoxin stimulates Na/K ATPase. Stimulation of Na/K ATPase increases intracellular concentration of Na⁺ ions. Increased intracellular Na⁺ decreases the Na⁺/Ca⁺⁺ exchanger and allows intracellular Ca⁺⁺ concentrations to increase. Increased intracellular Ca⁺⁺ increases the formation of actinomyosin and increases the force of myocardial contractions.
B) Digoxin binds to and inhibits Na/K ATPase. Inhibition of Na/K ATPase decreases intracellular concentration of Na⁺ ions. Decreased intracellular Na⁺ increases the Na⁺/ Ca⁺⁺ exchanger and allows intracellular Ca⁺⁺ concentrations to decrease. Decreased intracellular Ca⁺⁺ increases the formation of actinomyosin and increases the force of myocardial contractions.
C) Digoxin binds to and inhibits Na/K ATPase. Inhibition of Na/K ATPase increases intracellular concentration of Na⁺ ions. Increased intracellular Na⁺ decreases the Na⁺/ Ca⁺⁺ exchanger and allows intracellular Ca⁺⁺ concentrations to increase. Increased intracellular Ca⁺⁺ increases the formation of actinomyosin and increases the force of myocardial contractions.
D) None of these are correct