0000000000170797
AUTHOR
U. Förstermann
Inducible Nitric Oxide Synthase
Inducible nitric oxide synthase (iNOS, also named NOSII or NOS2) is a high-output Ca++-independent NOS whose expression can be induced in a wide range of cells and tissues by cytokines and other agents (for a review see …
Identification of the NO Synthase isoforms Expressed in Human Neutrophil Granulocytes, Megakaryocytes and Platelets
SummaryUsing Western blot and fluorescent immunocytochemistry, NOS III (or ecNOS) and NOS II (or iNOS), but no NOS I (or ncNOS), were identified in preparations of human platelets. Reverse-transcription polymerase chain reactions (RT-PCR) demonstrated NOS III mRNA, but no NOS II mRNA (which is short-lived) and no NOS I mRNA in platelets. Immunofluorescent staining of human bone marrow smears showed the presence of NOS III, but not NOS I in megakaryocytes. A subpopulation of megakaryocytes also expressed NOS II. In preparations of human neutrophils, immunocytochemistry demonstrated NOS I in all cells, whereas no NOS III was detected. The few NOS II positive cells were characterized as contam…
Endothelial Nitric Oxide Synthase
Endothelial nitric oxide synthase (eNOS; also referred to as NOS3 or NOSIII), a low output enzyme is the prototypical isoform being found in endothelial cells. This isoform (like nNOS) synthesizes NO in a short-lasting, pulsatile, Ca++/calmodulin-activated manner. Endothelium-derived NO is a physiologically significant vasodilator and inhibitor of platelet aggregation and adhesion. In addition, vascular NO can prevent leukocyte adhesion to the endothelium by down-regulating the leukocyte adhesion glycoprotein complex CD11/CD18. Finally, endothelial NO has also been shown to inhibit the proliferation of vascular smooth muscle cells. Therefore, endothelial NO is likely to represent a protecti…
Non-Vertebrate Nitric Oxide Synthases
NO is an important signalling molecule making essential contributions to innate immunity in mammals. Interestingly, also several non-vertebral NOS have been described. Aside from a role in the feeding of bloodsucking insects, NO has been shown, for example, to play an important role in Drosophila innate immunity …
Nitric Oxide Synthase(s)
NO synthases (NOS) represent a family of enzymes that catalyze the formation of nitric oxide (NO) from the amino acid L-arginine. In mammals, three isoforms of NOS have been identified …
Neuronal Nitric Oxide Synthase
Neuronal nitric oxides synthase (nNOS; also referred to as NOS1 or NOS I) is a low-output enzyme that is primarily expressed in neurons. Like eNOS, it is a low-output NOS whose activity is regulated by Ca++ and calmodulin, and that produces NO in a pulsatile fashion. nNOS has a widespread distribution in the central and peripheral nervous systems. In addition, nNOS mRNA transcripts and/or protein have also been detected in non-neuronal cell types, such as rhabdomyocytes, epithelial cells, mast cells, and neutrophils …
Nitric oxide synthase in the enteric nervous system of the guinea-pig: a quantitative description
The distribution and abundance of nitric oxide synthase (NOS)-containing neurons and their terminals in the gastrointestinal tract of the guinea-pig were examined in detail using NADPH diaphorase histochemistry and NOS immunohistochemistry. NOS-containing cell bodies were found in the myenteric plexus throughout the gastrointestinal tract and in the submucous plexus of the stomach, colon and rectum. NOS-containing neurons comprised between 12% (in the duodenum) and 54% (in the esophagus) of total myenteric neurons. In the ileum, NOS neurons represented 19% of total myenteric neurons. Most of the NOS neurons throughout the gastrointestinal tract possessed lamellar dendrites and a single axon…