GENERAL HISTOLOGY

Detailed explanation-1: -Vasodilation, also known as vasorelaxation, is the widening of blood vessels. It results from relaxation of smooth muscle cells within the vessel walls, in particular in the large veins, large arteries, and smaller arterioles.

Detailed explanation-2: -Arterioles provide blood to the organs and are chiefly composed of smooth muscle. The autonomic nervous system influences the diameter and shape of arterioles.

Detailed explanation-3: -Arteriolar dilators relax the smooth muscle of systemic arterioles, decreasing peripheral vascular resistance and impedance. This usually results in decreased systemic arterial blood pressure, systolic intraventricular pressure and systolic myocardial wall stress (or afterload).