Artemisia species, growing in almost all the northern hemisphere, is used in folk medicine of some countries as a remedy for hypertension. Since some cardiovascular disorders including hypertension are accompanied with altered responsiveness of vascular alpha-adrenergic receptors, the effect of aqueous Artemisia annua extract (100 and 200 mg kg-1) on a1-adrenoceptor agonist-induced contraction ...

Angiotensin II is a major endocrine hormone that affects directly both vascular smooth muscle and endothelial cells. Since vascular reactivity to angiotensin II changes in more physiological and pathophysiological conditions, the present study was performed to investigate the effect of intraperitoneal administration of angiotensin-converting enzyme inhibitor and captopril (30 and 50 mg kg-1, on...

PURPOSE Intravenous lipid emulsions have been used to treat the systemic toxicity of local anesthetics. The goal of this in vitro study was to examine the effects of lipid emulsions on the norepinephrine-mediated reversal of vasodilation induced by high doses of levobupivacaine, ropivacaine, and mepivacaine in isolated endothelium-denuded rat aorta, and to determine whether such effects are ass...

The presence of histamine H(3) receptors was evaluated on the rat aorta endothelium. In the presence of pyrilamine (1 nM, 7 nM, 10 nM) or thioperamide (1 nM, 10 nM, 30 nM) the concentration-response curve for histamine-induced (0.1 nM - 0.01 mM) endothelium-dependent rat aorta relaxation was shifted to the right without significant change of the E(max) indicating competitive antagonism by pyril...

In this study, the possible involvement of L-type voltage-operated calcium channels in the vasorelaxant effect of the flavonoid quercetin was investigated, using the isolated aortic rings from normal male rats. Addition of quercetin (0.1 µM-1 mM) caused a significant dose-dependent relaxation of noradrenaline (NA)- and KCl-preconstricted rings and nifedipine attenuated this response, especially...

We tried to determine alpha 1-adrenoceptor subtypes involved in noradrenaline-induced contractions of rat thoracic aorta and dog carotid artery. Prazosin competitively antagonized the contractions induced by noradrenaline in both the arteries with a high pKB value (approximately 9.7). WB4101, benoxathian, phentolamine, HV723 and 5-methylurapidil also competitively antagonized the responses to n...

AIMS C-type natriuretic peptide (CNP) and nitric oxide (NO) are endothelium-derived factors that play important roles in the regulation of vascular tone and arterial blood pressure. We hypothesized that NO produced by the endothelial NO-synthase (NOS-3) contributes to the relaxation induced by CNP in isolated rat aorta via activation of endothelial NPR-C receptor. Therefore, the aim of this stu...

We previously reported that adrenomedullin (AM), a potent vasodilator peptide discovered in pheochromocytoma cells, stimulates nitric oxide (NO) release in the rat kidney. To further investigate whether the NO-cGMP pathway is involved in the mechanisms of AM-induced vasodilation, we examined the effects of E-4021, a cGMP-specific phosphodiesterase inhibitor, on AM-induced vasorelaxation in aort...

The hypotensive effect of garlic has been well-documented in human subjects and animals. Since endothelial activity regulates vascular reactivity in physiological and pathophysiological conditions, the aim of the present study was to investigate the effect of garlic on endothelium-dependent and independent relaxation of rat aorta for elucidation of mechanism of the garlic anti-hypertensive effe...