We reported impaired endothelium-derived relaxation factor/nitric oxide (EDRF/NO) responses and constitutive nitric oxide synthase (cNOS) activity in subcutaneous vessels dissected from patients with essential hypertension (n = 9) compared with normal controls (n = 10). We now test the hypothesis that the patients in this study have increased circulating levels of the cNOS inhibitor, asymmetric...

Nitric oxide (NO), previously known as Endothelium-Derived Relaxing Factor (EDRF) is involved in a wide range of physiological and pathophysiological mechanisms. It is synthesized endogenously by the enzymes Nitric Oxide Synthase (NOS) in specialized tissues from its precursor L-arginine, yielding L-citrulline as a byproduct. It is released by a family of isoenzymes, viz., the endothelial (eNOS...

Phenylephrine-induced oscillatory contractions in rabbit mesenteric arteries were investigated in vitro. Adrenergic, cholinergic, or histamine antagonists as well as cyclooxygenase and lipoxygenase inhibitors had no effect on this phenylephrine-induced oscillation. The removal of extracellular calcium ions or treatment with a calcium antagonist reduced the amplitude and frequency of the oscilla...

various polymorphisms on endothelial nitric oxide synthase (enos) gene cause reduced production of no, the endothelial relaxing factor, and may accelerate the process of atherosclerosis. the study designed to investigate the frequency of t-786c polymorphism of the enos gene in patients suffering from coronary artery disease (cad) in north-west of iran. one hundred twenty subjects including 60 p...

Various polymorphisms on endothelial nitric oxide synthase (eNOs) gene cause reduced production of NO, the endothelial relaxing factor, and may accelerate the process of atherosclerosis. The study designed to investigate the frequency of T-786C polymorphism of the eNOs gene in patients suffering from coronary artery disease (CAD) in north-west of Iran. One hundred twenty subjects including 60 p...

There is now strong evidence that an endothelial mechanism, other than nitric oxide or prostacyclin, exists for dilating arteries and arterioles. This third pathway has been named endothelium-derived hyperpolarizing factor (EDHF) and should not be confused with endothelium-derived relaxing factor, which is nitric oxide. Currently, there are several ideas for the mechanism of EDHF, which may var...