The present study investigates the mechanisms related to the endogenous nitric oxide synthase (eNOS) activation in the relaxant effects of a proanthocyanidin-rich fraction (PRF), obtained from Croton celtidifolius Baill barks, in rat thoracic aorta rings with endothelium. In vessels pre-contracted with phenylephrine (Phe), PRF (0.1 - 100 microg/mL) induced a concentration-dependent relaxation. ...

This study examined the effects of quercetin on spontaneously contracting portal veins isolated from healthy young adult male and female Wistar rats (250-300 g). Quercetin (10(-7)-10(-4) M) always produced significant biphasic effects, comprising an initial brief stimulant effect (rise in basal tone), followed by a sustained, longer-lasting secondary relaxant (inhibitory) effect on the venous t...

Obesity is a major health care problem and is associated with significant cardiovascular morbidity. Leptin, a neuroendocrine hormone released by adipose tissue, is important in modulating obesity by signaling satiety and increasing metabolism. Moreover, leptin receptors are expressed on vascular endothelial cells (ECs) and mediate angiogenesis. We hypothesized that leptin may also play an impor...

1. The L-arginine-NO pathway has been implicated in the vasorelaxant effect of 17-beta-oestradiol. Here we have addressed the involvement of two distinct activation steps of endothelial nitric oxide synthase (eNOS) in the 17-beta-oestradiol-induced vasorelaxant effect on rat aortic rings. 2. Rat aortic rings contracted with phenylephrine (PE) 1 microM relaxed in a concentration related fashion ...

Viscum album leaf extract has a folk reputation as an antihypertensive agent in Nigeria. Evidence suggests that it has a relaxant effect on smooth muscle. The present study was designed to investigate the role of calcium in the vasorelaxant effect of this extract. Concentration response studies to noradrenaline, KCl and CaCl2 were carried out in rat aortic rings with and without the extract in ...

Rho-kinase has been suggested as a potential therapeutic target in the treatment of cardiovascular diseases. The Rho-kinase signaling pathway is substantially involved in vascular contraction. The aim of the present study was to evaluate the vasorelaxant effects of Rho kinase inhibitor DL0805 in isolated rat aortic rings and to investigate its possible mechanism(s). It was found that DL0805 exe...

Lectins are ubiquitous proteins in nature, with nonimmune origin, which have at least one non-catalytic domain that binds carbohydrates specifically and reversibly. They can be found in vegetables leaves, stems and seeds. The Dalbergieae tribe has lectins which have specificity for different carbohydrates and also have several biological activities such as induction of rat paw edema, release of...

The aim of the present study was to examine whether endocannabinoids cause PPARγ-mediated vascular actions. Functional vascular studies were carried out in rat aortae. Anandamide and N-arachidonoyl-dopamine (NADA), but not palmitoylethanolamide, caused significant vasorelaxation over time (2 hours). Vasorelaxation to NADA, but not anandamide, was inhibited by CB(1) receptor antagonism (AM251, 1...

The vasorelaxant effects of dealcoholized wild grape (Vitis coignetiae) wine were investigated with isolated rat thoracic aorta. In our present study, we demonstrate that wild grape wine powder (WGWP) induced relaxation of aortic rings preconstricted with norepinephrine in a dose-dependent manner (at concentrations ranging from 0.1 to 1 mg/mL). The vasorelaxant effect of WGWP was dependent on i...