Nitric Oxide

Nitric oxide, or nitrogen oxide, also known as nitrogen monoxide, is a molecule with chemical formula NO. It is a free radical and is an important intermediate in the chemical industry. Nitric oxide is a by-product of combustion of substances in the air, as in automobile engines, fossil fuel power plants, and is produced naturally during the electrical discharges of lightning in thunderstorms.

In mammals including humans, NO is an important cellular signaling molecule involved in many physiological and pathological processes. It is a powerful vasodilator with a short half-life of a few seconds in the blood. Long-known pharmaceuticals like nitroglycerine and amyl nitrite were discovered, more than a century after their first use in medicine, to be active through the mechanism of being precursors to nitric oxide.

Low levels of nitric oxide production are important in protecting organs such as the liver from ischemic damage.

Nitric oxide should not be confused with nitrous oxide (N2O), an anaesthetic and greenhouse gas, or with nitrogen dioxide (NO2), a brown toxic gas and a major air pollutant. However, nitric oxide is rapidly oxidised in air to nitrogen dioxide. Humphry Davy discovered this to his discomfort, when he inhaled the gas early in his career.

Despite being a simple molecule, NO is an important biological regulator and is a fundamental component in the fields of neuroscience, physiology, and immunology, with discovery of its key roles leading to Nobel Prize winning research in these areas. It was proclaimed “Molecule of the Year” in 1992.

Read more about Nitric Oxide:  Reactions, Production, Environmental Effects, Technical Applications, Biological Functions

Other articles related to "nitric oxide":

Atrial Natriuretic Peptide Receptor - Mechanism
... Instead, vascular endothelial cells will use L-arginine to make nitric oxide via nitric oxide synthase ... The nitric oxide will then diffuse into the vascular smooth muscle and will activate the soluble guanylyl cyclase ... The nitroglycerine will be metabolized to nitric oxide, which will stimulate soluble guanylyl cyclase ...
PGO Waves - Mechanism For PGO Wave Generation and Propagation - Modulatory Neurons - Nitroxergic Neurons
... Nitroxergic neurons use nitric oxide (NO) as a neurotrasmitter ... In theory, the increase of nitric oxide is seen as an excitatory neuromodulator in PGO wave generation ... This stems from animal testing that has shown increases in PGO waves as nitric oxide levels were increased in the pons ...
S-Nitrosothiol
... because they serve as donors of the nitrosonium ion NO+, and nitric oxide and some organic nitroso derivatives serve as signaling molecules in living systems, especially related to vasodilation ... S-Nitrosated proteins (SNOs) serve to transmit nitric oxide (NO) bioactivity and to regulate protein function through mechanisms analogous to phosphorylation ... Nitric oxide synthase (NOS) activity leads directly to SNO formation ...
Tendon Rupture - On-going Research Into New Treatments - Nitric Oxide
... Nitric oxide (NO) also appears to play a role in tendon healing and inhibition of its synthesis impairs tendon healing ... The use of a nitric oxide delivery system (glyceryl trinitrate patches) applied over the area of maximal tenderness was tested in three clinical trials for the ...
Nitric Oxide - Medical Use - Mechanism of Action - Pharmacokinetics
... Nitric oxide is absorbed systemically after inhalation ... Nitrate has been identified as the predominant nitric oxide metabolite excreted in the urine, accounting for >70% of the nitric oxide dose inhaled ...