The Unique Role of Nitric Oxide as a Widespread Signaling Molecule
The field of nitric oxide (NO) research has developed in explosive proportions since the discovery of endogenous NO in 1986. The first biologically important actions of NO were that nitroglycerin and related nitrovasodilators elicit vascular smooth muscle relaxation by liberating NO in the smooth muscle. NO relaxes smooth muscle by activating cytosolic guanylate cyclase and elevating smooth muscle levels of cyclic GMP. Soon thereafter, NO was found to inhibit platelet aggregation by mechanisms also involving cyclic GMP. NO acts as a neurotransmitter in the central and peripheral nervous systems, where NO modulates memory, learning, recall and erectile function. NO may function in a similar manner in the GI tract, airways and bladder. Based on these properties of NO, new drugs can be developed to treat hypertension, atherosclerosis, stroke, angina pectoris, heart failure, vascular complications of diabetes, GI ulcers, impotency and other vascular disorders…and there is much more to explore!