Fluorine F 18 NOS

**Semantic type:** Pharmacologic Substance

**Definition:** A radiotracer composed of an analog of the reversible nitric oxide synthase (NOS) inhibitor, 2-amino 4-methylpyridine, radiolabeled with fluorine F 18, with potential imaging activity upon positron emission tomography/computed tomography (PET/CT). Upon administration of fluorine F 18 NOS, the NOS moiety targets and binds to inducible NOS (iNOS). Upon PET/CT imaging, iNOS expression and thus the extent of inflammation can be assessed. iNOS expression is upregulated in a variety of inflammatory diseases and certain cancers and may invoke a chronic inflammatory state in tumor cells.

**Synonyms:** - (18)F-NOS - 18F NOS - 18F-NOS - FNOS - NOS F-18 - [18F]NOS