What is the mechanism of action for lisinopril in treating hypertension?

Lisinopril is an angiotensin-converting enzyme (ACE) inhibitor, and its primary mechanism of action is to inhibit the conversion of angiotensin I to angiotensin II. Angiotensin II is a potent vasoconstrictor that leads to increased blood pressure by causing blood vessels to narrow and stimulating the release of aldosterone, which promotes sodium and water retention. By inhibiting this conversion, lisinopril effectively reduces the levels of angiotensin II, leading to vasodilation and a decrease in blood pressure. This mechanism also helps reduce the workload on the heart and mitigate the harmful effects of hypertension on cardiovascular health.

The other options reflect different mechanisms of action not characteristic of lisinopril. Blocking calcium channels primarily pertains to calcium channel blockers, which function differently by preventing calcium from entering the cells of the heart and blood vessels, resulting in relaxation and lower blood pressure. Reducing heart rate through central nervous system effects is more typical of certain beta-blockers, not ACE inhibitors like lisinopril. Vasodilation can occur as a result of reduced angiotensin II levels, but it does not describe a direct action of lisinopril itself as it primarily operates through the inhibition of angiot