Endothelium-derived relaxing factor

The "endothelium-derived relaxing factor" is synonymous with"nitric oxide". The discovery of this factor and its identification as nitric oxide, which acts as an important cardiovascular signal molecule, led to the Nobel Prize in 1998. Although NO is a structurally simple heteronuclear diatomic molecule, it exhibits a number of complex biochemical effects that produce a wide range of biological effects. NO is a labile radical gas, which is produced continuously and on demand and acts as an endogenous mediator in controlling systemic and microvascular tone, myocardial contractility, cellular nitroso-reduction balance, inflammation, anticoagulation and growth responses in the cardiovascular system.

Since its discovery, however, there has been a growing awareness that the complexity of NO signal transduction is largely due to the effect of both small and large S-nitrosothiol species, which occur in spatially limited signal microdomains.