Nitric oxide synthase (Neuronal and Inducible) (nNOS/iNOS)

Nitric oxide synthases (NOS) are a family of enzymes that catalyze the production of nitric oxide (NO) from L-arginine (UniProt P29475, P35228). This target group comprises the neuronal isoform (nNOS or NOS1) and the inducible isoform (iNOS or NOS2). nNOS is primarily expressed in the nervous system and is involved in neurotransmission and synaptic plasticity, while iNOS is induced by inflammatory cytokines to produce large amounts of NO for immune defense (StatPearls, "Nitric Oxide Synthase", 2023). Dysregulation of nNOS is associated with neurodegenerative diseases and stroke, whereas overproduction of NO by iNOS is linked to chronic inflammation, autoimmune disorders, and septic shock (PubMed, "Nitric oxide synthases: structure, function and inhibition", 2011). Therapeutic development focuses on selective inhibitors that can reduce pathological NO levels without interfering with the cardiovascular homeostasis maintained by endothelial NOS (eNOS) (PubChem, "Nitric Oxide Synthase Inhibitors").

Other names

NOS1NOS2nNOSiNOSNitric oxide synthase 1Nitric oxide synthase 2Neuronal NOSInducible NOSbNOSHEP-NOS

Competitive inhibition of the L-arginine binding site or interference with the heme-binding domain to prevent the conversion of L-arginine to L-citrulline and nitric oxide (StatPearls, 2023).