Pharmacology · single question
Which of the following BEST describes the mechanism of action of atenolol?
Show answer and explanation
Correct answer: D. Cardioselective beta-1 blocker
- A. Alpha-1 blockers (e.g., prazosin, doxazosin) reduce peripheral vascular resistance; this is not the mechanism of atenolol.
- B. Calcium channel blockers (e.g., amlodipine, nifedipine) prevent calcium influx into cardiac and vascular smooth muscle — not the mechanism of atenolol.
- C. Non-selective beta blockers (e.g., propranolol) block both beta-1 (cardiac) and beta-2 (pulmonary/vascular) receptors. Atenolol is selective.
- D. Correct. Atenolol is a cardioselective beta-1 blocker. It preferentially blocks beta-1 adrenergic receptors in the heart, reducing heart rate and blood pressure, with less effect on beta-2 receptors in the bronchi.