OBJECTIVES The study was designed to evaluate the functional impact of nitric oxide (NO) generation within the myocardium on cardiac contraction in the failing human heart. BACKGROUND Heart failure is associated with activation of cytokines and expression of inducible nitric oxide synthase (NOS II), which generates NO from L-arginine. Nitric oxide has been shown to modulate myocardial perform...

Cerebral ischaemia results in the activation of three isoforms of NOS (nitric oxide synthase) that contribute to the development of and recovery from stroke pathology. This review discusses, in particular, the role of the transcriptionally activated NOS-2 (inducible NOS) isoform and summarizes the outcomes of experimental stroke studies with regard to the therapeutic utility of nitric oxide don...

Prevention and treatment of cardiovascular disorders by HMG-CoA reductase inhibitors (or statins), beyond their lipid-lowering properties, have been demonstrated including activation of the endothelial nitric oxide synthase (eNOS). Beside endothelial cells, red blood cells (RBCs) possess NOS and produce nitric oxide (NO), which contributes to RBC deformability. The present study tested the capa...

The expression of nitric oxide synthase (NOS) isoforms in the ovaries of pigs was examined to study the involvement of nitric oxide, a product of NOS activity, in the function of the ovary. Western blot analysis detected three types of NOS in the ovary, including constitutive neuronal NOS (nNOS), endothelial NOS (eNOS) and inducible NOS (iNOS); eNOS immunoreactivity was more intense compared wi...

Nitrergic neurons of the dorsal raphe nucleus (DRN) may play a role in physiological stress responses. The caudal lateral wings (CLW) are unique compared to other rostral-caudal DRN sub-regions because they contain distinct nitric oxide (NO) synthase (NOS) populations that are independent of tryptophan hydroxylase (TPH). NOS neurons in the CLW are also highly activated during acute restraint st...

BACKGROUND Nitric oxide synthase (NOS) is negatively regulated by protein-protein interactions with caveolin-1 before extracellular activating signals release it for nitric oxide (NO) production. Smooth muscle protein kinase G (PKG) is a down-stream effector of NO signaling for relaxation of vascular smooth muscle cells (SMC). The PKG is also found in endothelial cells and it inhibits activated...

Nitric-oxide synthases (NOS, EC 1.14.13.39) are hemeproteins that catalyze oxidation of L-arginine to NOz and L-citrulline. Three main isozymes exist in mammals that are regulated by distinct genes (1–6): a constitutive neuronal NOS (nNOS or NOS I), (7, 8), an endotoxinand cytokine-inducible NOS (iNOS or NOS II) (9, 10), and a constitutive endothelial NOS (eNOS or NOS III) (11). Although NOS ha...

BACKGROUND Myenteric interneurones are involved in the reflexes that control the motility of the human colon. AIMS The distribution of choline acetyltransferase (ChAT) and nitric oxide synthase (NOS) immunoreactivity in myenteric interneurones was investigated in this study. METHODS DiI (1,1'- didodecyl 3,3,3',3'-indocarbocyanine perchlorate) was applied to the myenteric plexus of the human...

Exposure of primary cultures of neonatal rat cortical astrocytes to bacterial lipopolysaccharide (LPS) results in the appearance of nitric oxide synthase (NOS) activity. The induction of NOS, which is blocked by actinomycin D, is directly related to the duration of exposure and dose of LPS, and a 2-hr pulse can induce enzyme activity. Cytosol from LPS-treated astrocyte cultures, but not from co...

The nitric oxide synthase (NOS) inhibitor nitro-L-arginine augmented the contractions to angiotensin (Ang) II in carotid artery rings without endothelium from spontaneously hypertensive rats (SHR) but not normotensive Wistar-Kyoto rats, suggesting the possibility of nonendothelial NOS activity in SHR arteries. In SHR artery without endothelium, the potentiation of Ang II contraction by nitro-L-...