Search results for "Endothelial NOS"
showing 4 items of 24 documents
NMDA-induced acetylcholine release in mouse striatum: role of NO synthase isoforms
2002
Striatal cholinergic interneurons are stimulated by glutamatergic inputs from thalamus and cortex via NMDA receptors. The present microdialysis study was designed to characterize the role of nitric oxide (NO) in this process and to identify the NO synthase (NOS) isoform responsible for this effect. For this purpose, we studied the effects of NMDA and 3-morpholino sydnonimine (SIN-1) perfusions on the release of acetylcholine (ACh) in mouse striatum. In wild-type C57/Bl6 mice, perfusion of NMDA (100 µm) induced a two-fold stimulation of ACh release. This effect was attenuated in mice lacking endothelial NOS but was completely absent in mice lacking neuronal NOS. Local perfusion of SIN-1 (300…
Nitric Oxide Synthesis in Vascular Physiology and Pathophysiology
2015
Nitric oxide (NO) is produced by three NO synthase (NOS) isoforms: neuronal NOS (nNOS), inducible NOS (iNOS), and endothelial NOS (eNOS). Under physiological conditions, vascular NO is produced by eNOS and nNOS, with both playing atheroprotective roles. Under pathological conditions, iNOS can be induced and eNOS may become uncoupled. iNOS produces a large amount of NO, induces vascular dysfunction, and promotes atherogenesis. Uncoupled eNOS generates superoxide instead of NO and contributes significantly to endothelial dysfunction and atherogenesis. Major mechanisms of eNOS uncoupling include depletion of tetrahydrobiopterin, an essential co-factor for the eNOS enzyme, and deficiency of L-a…
Nitric oxide synthases: regulation and function
2011
Nitric oxide (NO), the smallest signalling molecule known, is produced by three isoforms of NO synthase (NOS; EC 1.14.13.39). They all utilize l-arginine and molecular oxygen as substrates and require the cofactors reduced nicotinamide-adenine-dinucleotide phosphate (NADPH), flavin adenine dinucleotide (FAD), flavin mononucleotide (FMN), and (6R-)5,6,7,8-tetrahydrobiopterin (BH(4)). All NOS bind calmodulin and contain haem. Neuronal NOS (nNOS, NOS I) is constitutively expressed in central and peripheral neurons and some other cell types. Its functions include synaptic plasticity in the central nervous system (CNS), central regulation of blood pressure, smooth muscle relaxation, and vasodila…
Nitric oxide in the pathogenesis of vascular disease
2000
Nitric oxide (NO) is synthesized by at least three distinct isoforms of NO synthase (NOS). Their substrate and cofactor requirements are very similar. All three isoforms have some implications, physiological or pathophysiological, in the cardiovascular system. The endothelial NOS III is physiologically important for vascular homeostasis, keeping the vasculature dilated, protecting the intima from platelet aggregates and leukocyte adhesion, and preventing smooth muscle proliferation. Central and peripheral neuronal NOS I may also contribute to blood pressure regulation. Vascular disease associated with hypercholesterolaemia, diabetes, and hypertension is characterized by endothelial dysfunct…