Recent studies using chemiluminescence and spectrophotometry have shown that cultured and native endothelial cells release nitric oxide (NO). Pharmacological and biochemical evidence argue for and against the proposal that endothelium-derived relaxing factor (EDRF) is identical with free NO. In an attempt to identify EDRF as free NO, a bioassay technique was combined with an NO trap (hemoglobin...

About 10 years ago, Furchgott and Zawadzki2 /... made a remarkable observation that helped .Lk.clarify variable effects of acetylcholine on arterial tone. They demonstrated that isolated arteries relaxed in response to acetylcholine and other endogenous vasoactive agents only in the presence of an intact endothelium and postulated that endothelial cells released a diffusible vasodilator princip...

Endothelin-1 is a 21-amino acid endothelial vasoconstrictor peptide that may be the physiological antagonist of endothelium-derived relaxing factor (EDRF). Endothelin-1 (10(-11)-3 x 10(-7) M) evoked potent contractions of isolated internal mammary arteries, internal mammary veins, and saphenous veins, which were enhanced in internal mammary veins as compared with internal mammary arteries (conc...

Nitric oxide is a key intercellular messenger in the human and animal bodies. The identification of nitric oxide (NO) as the endothelium-derived relaxing factor (EDRF) has driven an enormous effort to further elucidate the chemistry, biology and therapeutic actions of this important molecule. It has found that nitric oxide is involved in many disease states such as such as chronic heart failure...

BACKGROUND AND PURPOSE Stimulation of P2u purinoceptors by UTP on endothelium dilates the rat middle cerebral artery (MCA) through the release of endothelium-derived relaxing factor/nitric oxide (EDRF/NO) and an unknown relaxing factor. The purpose of this study was to determine whether this unknown relaxing factor is endothelium-derived hyperpolarizing factor (EDHF). METHODS Rat MCAs were is...

Even five years ago few could have realised that the simple gas nitric oxide (NO) would be involved in the regulation of so many physiological functions and pathophysiological processes. There has been an explosion of information about nitric oxide which appears to be involved in an extraordinary range of functions including vascular regulation, neurotransmission, host defence, and cytotoxicity...

This review discusses the role of three mediators, synthesized by vascular endotheiial cells, that help to keep the surface of the normal endotheliuin nonthrombogenic. The first is prostacydin, a product of arachldonic add metabolism discovered hi 1976. This labile prostanoid, with a half-life of approximately 3 minutes, relaxes vascular smooth musde and inhibits the aggregation of blood platel...

BACKGROUND Nitric oxide (NO), a small effector molecule produced enzymatically from L-arginine by nitric oxide synthase (NOS), is a mediator not only of important homeostatic mechanisms (e.g., blood vessel tone and tissue perfusion), but also of key aspects of local and systemic inflammatory responses. Previous efforts to develop inhibitors of NOS to protect against NO-mediated tissue damage in...

The purpose of this review is to provide the anaesthetists with a comprehensive update on the endothelial-cell control of local blood flow. This single cell layer was originally thought to represent only a passive barrier. It is now evident that it plays an active role in a broad variety of biological functions. Since the discovery of the endothelial-derived relaxing factor (EDRF), it has been ...

This review discusses the role of three mediators, synthesized by vascular endothelial cells, that help to keep the surface of the normal endothelium nonthrombogenic. The first is prostacyclin, a product of arachidonic acid metabolism discovered in 1976. This labile prostanoid, with a half-life of approximately 3 minutes, relaxes vascular smooth muscle and inhibits the aggregation of blood plat...