How do ACE inhibitors reduce blood pressure?

How do ACE inhibitors reduce blood pressure?

• A. They block the enzyme that forms angiotensin II, reducing arterial constriction
• B. They block calcium channels
• C. They increase aldosterone release
• D. They stimulate the renin-angiotensin system

Answer: (A)

ACE inhibitors lower blood pressure by blocking the enzyme that converts angiotensin I to angiotensin II. With less angiotensin II, there is reduced vasoconstriction of the arteries and less aldosterone release from the adrenal glands, which means less sodium and water retention. Additionally, ACE inhibitors raise levels of bradykinin, another vasodilator, which helps further lower vascular resistance. The other options describe actions not responsible for the effect: blocking calcium channels is a separate mechanism (calcium channel blockers), increasing aldosterone would raise blood pressure, and stimulating the renin-angiotensin system would increase angiotensin II and BP.

ACE inhibitors lower blood pressure by blocking the enzyme that converts angiotensin I to angiotensin II. With less angiotensin II, there is reduced vasoconstriction of the arteries and less aldosterone release from the adrenal glands, which means less sodium and water retention. Additionally, ACE inhibitors raise levels of bradykinin, another vasodilator, which helps further lower vascular resistance. The other options describe actions not responsible for the effect: blocking calcium channels is a separate mechanism (calcium channel blockers), increasing aldosterone would raise blood pressure, and stimulating the renin-angiotensin system would increase angiotensin II and BP.