Table 1

‚ÄÉNitric oxide synthase enzymes

NOS isoformsNumerical designationOther designationExpressionRegulationNO outputChromosome
NO, nitric oxide; NOS, nitric oxide synthase; nNOS, neural nitric oxide synthase; iNOS, inducible nitric oxide synthase; eNOS, endothelial nitric oxide synthase; CaM, calmodulin.
Type I1nNOSConstitutiveCalcium/CaMLow (picomol)12
Type II2iNOSInducibleInduced by cytokines, endotoxin, and oxidantsHigh (nanomol)17
Type III3eNOSConstitutiveCalcium/CaMLow (picomol)7