Explore the Nitric Oxide Knowledge Center and Learn about the many Functions of Nitric Oxide

home-illo3.testSince the original demonstration of the vasodilatory properties of Nitric Oxide nearly 30 years ago, it is now known that Nitric Oxide also regulates other aspects of cardiovascular physiology as well as playing a role in inflammatory and immune responses, reproductive functions, bronchodilation, bone formation, insulin sensitivity, and gastrointestinal protection.1

It’s Important to Know Nitric Oxide

Nitric oxide is a remarkable molecule with an important role in many physiologic processes that maintain human health. Although simple in chemical structure, the biological actions of Nitric Oxide are complex. In the late 1970s and early 1980s, Robert Furchgott described a key biologic function of compound, called  endothelium-derived relaxing factor (EDRF), that was produced by blood vessels with intact endothelium in response to acetylcholine.2 It was discovered that EDRF is produced by vascular endothelial cells and acts on underlying vascular smooth muscle cells to produce vasodilation. In the same period, Ferid Murad was studying the activation of soluble guanylyl cyclase (sGC) by nitrogen-containing compounds and the role of cyclic guanosine monophosphate (cGMP) in the relaxation of arterial smooth muscle.3 Later in 1987, Salvador Moncada and Louis Ignarro separately proved that EDRF was, in fact, NO which acts intracellularly through the activation of cGMP.4,5

Molecule of the Year

In 1992, Science designated Nitric Oxide as “Molecule of the Year” for its versatility and importance as a signaling molecule.6 Some consider the discovery of Nitric Oxide to be the greatest achievement in vascular biology in the latter part of the 20th century. This discovery culminated in the 1998 Nobel Prize in Physiology or Medicine awarded to the scientists (Drs. Furchott, Ignarro, and Murad) who pioneered the uncovering of Nitric Oxide function and fostered its application to medical science.7,8 Recently, Dr. Salvador Moncada was knighted by the Queen of England for his seminal and continued work in the field of Nitric Oxide biology.9

References: 1. Giles TD. Aspects of nitric oxide in health and disease: a focus on hypertension and cardiovascular disease. J Clin Hypertens. 2006;8(12 suppl 4):2-16. 2. Furchgott RF, Zawadzki JV. The obligatory role of endothelial cells in the relaxation of arterial smooth muscle by acetylcholine. Nature. 1980;288(5789):373-376. 3. Katsuki S, Arnold W, Mittal C, Murad F. Stimulation of guanylate cyclase by sodium nitroprusside, nitroglycerin and nitric oxide in various tissue preparations and comparison to the effects of sodium azide and hydroxylamine. J Cyclic Nucleotide Res. 1977;3(1):23-35. 4. Ignarro LJ, Buga GM, Wood KS, Byrns RE, Chaudhuri G. Endothelium-derived relaxing factor produced and released from artery and vein is nitric oxide. Proc Natl Acad Sci USA. 1987;84(24):9265-9269. 5. Palmer RM, Ferrige AG, Moncada S. Nitric oxide release accounts for the biological activity of endothelium-derived relaxing factor. Nature. 1987;327(6122):524-526. 6. Koshland DE Jr. The molecule of the year. Science. 1992;258(5090):1861. 7. Stuart-Smith K. Demystified. Nitric oxide. Mol Pathol. 2002;55(6):360-366. 8. The Nobel Prize in Physiology or Medicine 1998. Nobel Foundation Web site. http://nobelprize.org/nobel_prizes/medicine/laureates/1998. Accessed January 7, 2010. 9. New Year Honours—United Kingdom. London Gazette. December 30, 2009:N1. http://www.london-gazette.co.uk/issues/59282/supplements/1. Accessed February 2, 2010.