Final answer:
Nitroglycerin is the vasodilator most commonly used to ease the pain of angina. It releases nitric oxide, a known vasodilator, to relax the smooth muscle in the coronary vessels.
Step-by-step explanation:
The vasodilator most commonly used to ease the pain of angina is Nitroglycerin. Nitroglycerin is administered sublingually (under the tongue) to facilitate its absorption. It works by releasing nitric oxide, which is a known vasodilator, and endothelium-derived releasing factor to relax the smooth muscle in the coronary vessels.