How does amlodipine work in treating hypertension?

Amlodipine is a calcium channel blocker that primarily works by dilating peripheral arteries and relaxing vascular smooth muscle. This mechanism reduces the resistance that the heart has to work against when pumping blood, leading to a decrease in blood pressure. By inhibiting the influx of calcium ions into vascular smooth muscle cells, amlodipine causes these muscles to relax, resulting in vasodilation. This vasodilation decreases total peripheral resistance, which is effective in managing hypertension.

The other choices do not accurately describe the mechanism of action of amlodipine. Diuresis relates more to medications that promote the excretion of sodium and water, typically associated with diuretics, rather than calcium channel blockers. The perception of pain is not influenced by the actions of amlodipine, as it does not play a role in pain modulation. Lastly, while the renin-angiotensin system is an important pathway in blood pressure regulation, amlodipine does not block the conversion of angiotensin I to angiotensin II; that function is primarily associated with ACE inhibitors. Thus, the action of amlodipine distinctly revolves around vascular smooth muscle relaxation and arterial dilation.