Which statement describes the mechanism of ARBs?

Which statement describes the mechanism of ARBs?

• A. Inhibit calcium entry into vascular smooth muscle and cardiac myocytes
• B. Block angiotensin II from binding to AT1 receptors
• C. Block beta adrenergic receptors
• D. Inhibit angiotensin converting enzyme

Answer: (B)

ARBs work by blocking angiotensin II from binding to the AT1 receptor. This prevents the usual effects of angiotensin II—vasoconstriction, aldosterone secretion (which promotes sodium and water retention), and increased sympathetic activity—leading to lower blood pressure and reduced fluid retention. Because the AT1 receptor is blocked, angiotensin II cannot exert these actions, while AT2 receptors can still be stimulated, which may have other beneficial effects. This is different from calcium channel blockers, which prevent calcium entry into vascular smooth muscle and cardiac cells to cause vasodilation; it’s different from beta-blockers that inhibit beta-adrenergic receptors; and it’s different from ACE inhibitors, which reduce the production of angiotensin II by inhibiting the angiotensin-converting enzyme.

ARBs work by blocking angiotensin II from binding to the AT1 receptor. This prevents the usual effects of angiotensin II—vasoconstriction, aldosterone secretion (which promotes sodium and water retention), and increased sympathetic activity—leading to lower blood pressure and reduced fluid retention. Because the AT1 receptor is blocked, angiotensin II cannot exert these actions, while AT2 receptors can still be stimulated, which may have other beneficial effects.

This is different from calcium channel blockers, which prevent calcium entry into vascular smooth muscle and cardiac cells to cause vasodilation; it’s different from beta-blockers that inhibit beta-adrenergic receptors; and it’s different from ACE inhibitors, which reduce the production of angiotensin II by inhibiting the angiotensin-converting enzyme.