Outline the Steps in the Mechanism of Action of Digoxin

question 5

Multiple Choice

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

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Definitions:

Basilar Membrane

The basilar membrane is a structure in the cochlea of the inner ear; it plays a crucial role in the sense of hearing by facilitating the conversion of sound vibration into neural signals.

Kinesthesis

The sense of muscle movement and position, allowing individuals to perceive their body's actions and location even without visual cues.

Audition

The sense of hearing; the process by which sound waves are detected and interpreted by the brain.

Sensory Interaction

The process by which multiple sensory modalities interact to influence perception and behavior, such as how taste and smell combine to create flavor.