What is the mechanism of action for Amlodipine?

Amlodipine is a calcium channel blocker that primarily targets L-type calcium channels in vascular smooth muscle. By inhibiting these channels, it leads to decreased intracellular calcium levels, which in turn causes relaxation of the smooth muscle in blood vessels. This relaxation results in vasodilation, which lowers blood pressure and reduces the workload on the heart. Amlodipine is specifically effective in treating hypertension and angina due to its ability to facilitate blood flow and lower systemic vascular resistance.

The other options describe mechanisms not applicable to amlodipine. For instance, a direct vasodilator would work through mechanisms other than calcium channel blockade. Beta-receptor antagonism refers to the action of beta blockers, which is different from that of calcium channel blockers like amlodipine. Diuretics work by promoting urine production to reduce blood volume, which is a distinct mechanism altogether from the way amlodipine functions to lower blood pressure.