Abstract

Since its recognition as an endothelium-derived relaxing factor, the control and consequences of nitric oxide (NO) production has been investigated intensely. NO is not simply a vasodilator or regulator of smooth muscle tone but is a potent anti-platelet agent, neuromodulator and regulator of gene expression. This article reviews the mechanisms (intracellular Ca2+, phosphorylation and protein-protein interaction) that regulate the activity of each of the NO synthase isoforms and describes the physiology of NO in the circulation, kidney, skeletal muscle as well as in endocrine, immune and nervous systems.

Keywords: blood pressure, gene expression, phosphorylation, platelets, protein-protein association, reactive oxygen species, signal transduction, vascular tone