1. The contractile responses to endothelin-1 and the effect on these of various magnesium concentrations, were studied in isolated aortic rings from normotensive Sprague-Dawley rats and deoxycorticosterone acetate-salt (DOCA-salt) hypertensive rats. 2. Contractions induced by endothelin-1 were smaller in endothelium-denuded aortae from DOCA-salt hypertensive rats than in those from normotensive...

We have previously reported the production of endothelin, a potent vasoconstrictor peptide, by porcine cerebral microvessel endothelia and suggested its important role in the regulation of local blood flow within the brain. In our present study, radioimmunoassay with anti-porcine endothelin antiserum revealed that endothelin, produced by cerebral microvessel endothelia grown on a filter, is rel...

The aim of this study was to identify the role of chymase in the conversion of exogenously administered Big endothelin-1 in the mouse in vivo. Real-time polymerase chain reaction analysis detected mRNA of mucosal mast cell chymases 4 and 5, endothelin-converting enzyme 1a, and neutral endopeptidase 24.11 in pulmonary, cardiac, and aorta homogenates derived from C57BL/6J mice, with the latter ti...

This study was designed to assess whether blocking endogenous endothelin with anti-endothelin antibodies could alter the development of hypertension in stroke-prone spontaneously hypertensive rats (SHR) and DOCA-salt treated rats. Specific anti-endothelin antibodies were produced in rabbits by standard methods. The amount of anti-endothelin antibodies employed in this study blocked the hyperten...

Plasma concentrations of big endothelin-1 were determined by ELISA in 18 patients with complicated Plasmodium falciparum malaria in Bangkok. Before therapy, elevated levels were recorded (21 +/- 12 vs. 2.9 +/- 1.1 pmol/L in age- and sex-matched healthy subjects; P < .001). Even 7 days after therapy, elevated concentrations were seen (25 +/- 14 pmol/L). Plasma endothelin levels were correlated w...

We have recently demonstrated that chronic infusion of exogenous ANG II, which induces blood pressure elevation, attenuates renal medullary endothelin B (ET(B)) receptor function in rats. Moreover, this was associated with a reduction of ET(B) receptor expression in the renal inner medulla. The aim of this present work was to investigate the effect of a physiological increase in endogenous ANG ...

The endothelin-1 vasoconstrictor pathway contributes to age-related elevations in resting peripheral vascular tone primarily through activation of the endothelin subtype A (ET(A)) receptor. However, the regulatory influence of ET(A)-mediated vasoconstriction during exercise in the elderly is unknown. Thus, in 17 healthy volunteers (n = 8 young, 24±2 years; n = 9 old, 70±2 years), we examined le...

BACKGROUND Endothelin is an endothelium-derived peptide that produces sustained contraction of arterial and venous smooth muscle in vitro. Several studies have established endothelin as a systemic, renal, and coronary vasoconstrictor in vivo at pharmacological concentrations. Such concentrations of endothelin were antinatriuretic in association with activation of the renin-angiotensin-aldostero...

Endothelin ETA receptor couples to Gq/11 protein that transduces a variety of receptor signals to modulate diverse cellular responses including Ca mobilization. Stimulation of endothelin ETA receptor with endothelin-1 is generally believed to induce an increase in intracellular Ca concentration ([Ca]i) via Gq/11 protein. Here we provide the first convincing evidence that endothelin-1 elicited G...

OBJECTIVES The aim of this study was to investigate whether endothelin-1, acting locally, regulates arterial distensibility, assessed by measuring pulse-wave velocity in vivo. BACKGROUND Arterial stiffness is a key determinant of cardiovascular risk. Several lines of evidence support a role for the endothelium in regulating arterial stiffness by release of vasoactive mediators. However, the r...