What is the primary function of ACE inhibitors?

• A. To increase blood pressure
• B. To lower blood pressure by inhibiting the angiotensin-converting enzyme
• C. To enhance oxygen delivery to tissues
• D. To stimulate heart rate

Answer: (B)

The primary function of ACE inhibitors is to lower blood pressure by inhibiting the angiotensin-converting enzyme (ACE). ACE is an essential component of the renin-angiotensin-aldosterone system (RAAS), which plays a crucial role in regulating blood pressure. When ACE is inhibited, the conversion of angiotensin I to angiotensin II is reduced. Angiotensin II is a potent vasoconstrictor and also stimulates the secretion of aldosterone, leading to increased sodium and water retention, which raises blood pressure. By inhibiting this process, ACE inhibitors cause vasodilation, decrease blood volume, and ultimately lower blood pressure. This mechanism makes them effective in treating conditions such as hypertension and heart failure.

The other options do not accurately describe the primary action of ACE inhibitors. For instance, increasing blood pressure and stimulating heart rate are contrary to the effects of ACE inhibitors. Enhancing oxygen delivery to tissues is more associated with other types of medications, rather than the role of ACE inhibitors in managing blood pressure.