A 55-year-old woman with a long history of poorly controlled essential hypertension had recently added atenolol to her therapeutic regimen. Which of the following was most likely a primary mechanism that mediated the antihypertensive effect of atenolol in this patient?

Correct Answer: B

Rationale: The correct answer is B: Inhibition of epinephrine release from the adrenal medulla. Atenolol is a beta-blocker that primarily works by blocking beta-adrenergic receptors, leading to decreased release of epinephrine and norepinephrine. This results in reduced heart rate, cardiac output, and renin release, leading to decreased blood pressure. A: Dilation of large veins is not the primary mechanism of action of atenolol. It primarily affects the heart and vasculature by blocking beta-receptors. C: While atenolol does block beta receptors in the vascular wall, the primary mechanism of antihypertensive effect is through inhibition of epinephrine release. D: Atenolol does not directly affect sympathetic outflow from the vasomotor area. The main mechanism is through blocking beta-receptors and reducing catecholamine release.

Correct Answer: D

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: D

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: A

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: A

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.