Detection of endothelial cell-derived nitric oxide: current trends and future directions.

The vascular endothelium is a significant site of NO release that inhibits cellular adhesion and maintains a non-thrombogenic surface. Use of newly described technology suggests for the first time that the maximal release of NO induced by cNOS and iNOS activation may be quite similar, implying that it is the duration of NO release and not the concentration of NO produced from stimulated endothelial cells that accounts for the different biological activities of the enzymes. The respective roles of cNOS and iNOS must be carefully evaluated since both enzymes may have potent biological effects at local sites of production.