Which of the Following Accurately Describes the Mechanism of Action

question 13

Multiple Choice

Which of the following accurately describes 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 activity of 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 activity of 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 activity of 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 the above are correct.

---

Definitions:

Emotion

Emotion is a complex psychological state involving three distinct components: a subjective experience, a physiological response, and a behavioral or expressive response.

Mood

A temporary state of mind or feeling that affects an individual's emotional and psychological well-being.

Cannon-Bard Theory

A theory in psychology proposing that emotional feelings and physiological reactions to stimuli occur simultaneously and independently.

James-Lange Theory

A psychological theory suggesting that emotions result from physiological reactions to external events before the emotional experience occurs.