AGT and Hypertension: At the same time, the vascular endothelium, which normally produces NO as a protective mechanism of vasodilation and inhibition of leukocyte adhesion [19], with aging and hypertension, produces vasoactive molecules such as endothelin-1 (ET-1), angiotensin II (Ang II), and COX-derived prostanoid and superoxide anions that prevent vasodilation [17].