Search results for " Smooth"

Dexamethasone upregulates Nox1 expression in vascular smooth muscle cells.

2014

<b><i>Background/Aim:</i></b> It has been demonstrated that dexamethasone-induced hypertension can be prevented by the NADPH oxidase inhibitor apocynin. The effect of dexamethasone on NADPH oxidase, however, is unknown. The present study was conducted to investigate the effect of dexamethasone on the gene expression of Nox1, the major NADPH oxidase isoform in vascular smooth muscle cells. <b><i>Results:</i></b> Oral treatment of Wistar-Kyoto rats with dexamethasone (0.03 mg/kg/day) for 12 days led to an upregulation of Nox1 mRNA expression in the aorta. In cultured A7r5 rat aortic smooth muscle cells, dexamethasone increased Nox1 mRNA expressi…

Fludarabine prevents smooth muscle proliferation in vitro and neointimal hyperplasia in vivo through specific inhibition of STAT-1 activation.

2007

Drug-eluting stents are increasingly used to reduce in-stent restenosis and adverse cardiac events after percutaneous coronary interventions. However, the race for the ideal drug-eluting stent is still on, with special regard to the best stent-coating system and the most effective and less toxic drug. Fludarabine, a nucleoside analog, has both anti-inflammatory and antiproliferative cellular effects. The aim of the present study was to assess the cellular and molecular effects of fludarabine on vascular smooth muscle cell (VSMC) growth in vitro and in vivo and the feasibility and efficacy of a fludarabine-eluting stent. To study the biomolecular effects of fludarabine on VSMC proliferation…

Effect of testosterone on intracellular Ca++ in vascular smooth muscle cells.

2001

Increased responsiveness of human pulmonary arteries in patients with positive bronchodilator response.

1996

Abstract 1. The effects of noradrenaline, endothelin-1, acetylcholine and sodium nitroprusside were studied in isolated pulmonary arteries obtained from 14 patients undergoing lobectomy for lung carcinoma. Seven patients had shown increased response to a bronchodilator test prior to operation. In the remaining patients (control) the bronchodilator test was negative. 2. Artery rings from patients with a positive bronchodilator response showed greater contraction to noradrenaline (pD2 = 6.44 +/- 0.1; Emax = 93 +/- 9% of response to 100 mM KCl) and endothelin-1 (pD2 = 8.92 +/- 0.1; Emax = 130 +/- 16%) than the rings from control patients (pD2 = 6.04 +/- 0.08; Emax = 56 +/- 8% for noradrenaline…

Anatomical differences in responsiveness to vasoconstrictors in the mesenteric veins from normal and portal hypertensive rats

1996

The present study evaluates the effects of pre-hepatic portal hypertension, induced in rats by partial portal vein ligation, on the responsiveness of rostral (proximal) and caudal (distal) rings from the mesenteric vein. The anatomical origin of the sample influenced the response to vasoconstrictors in sham-operated animals, and this pattern of reactivity was specifically modified in portal-ligated rats. In veins from sham-operated rats, contraction induced by a submaximal concentration of KCl (60 mM) was greater in proximal than in distal rings. Vasopressin and 5-hydroxytryptamine contracted mainly distal rings, methoxamine showed a greater effect on proximal rings, and endothelin-1 and an…

Actions of alpha-adrenoceptor blocking agents on two types of intracellular calcium stores mobilized by noradrenaline in rat aorta.

1993

In isolated rat aortic strips noradrenaline induces a biphasic contractile response in Ca-free medium, associated with two different intracellular calcium pools, one of which is common to caffeine. We analyzed the mechanisms involved in the depletion and repletion of both intracellular Ca pools sensitive to noradrenaline in different experimental procedures in presence of prazosin, phentolamine and yohimbine. At 37 degrees C the alpha-adrenergic blocking agents inhibited contractile responses to noradrenaline in Ca-free medium, with prazosin being highly selective. alpha 2-adrenoceptors probably do not participate in the release of Ca from internal stores, as no contractile response was obs…

Evidence for a role of inducible nitric oxide synthase in gastric relaxation of mdx mice

2006

Alterations of gastric mechanical activity have been reported in mdx mouse, animal model for Duchenne muscular dystrophy. This study examined if alterations in the vasoactive intestinal polypeptide (VIP) system are present in mdx stomach. Gastric mechanical activity was recorded in vitro as changes of endoluminal pressure and neurally or pharmacologically evoked relaxations were analysed in mdxvs normal stomach. Reverse-transcription polymerase chain reaction was used to detect inducible nitric oxide synthase (iNOS) expression. Relaxations to sodium nitroprusside in mdx stomach showed no difference in comparison with normal preparations. In normal stomach, VIP produced relaxation, which was…

Functional evidence for different roles of GABAA and GABAB receptors in modulating mouse gastric tone

2010

Abstract The aims of the present study were to investigate, using mouse whole stomach in vitro , the effects of γ-aminobutyric acid (GABA) and GABA receptor agonists on the spontaneous gastric tone, to examine the subtypes of GABA receptors involved in the responses and to determine the possible site(s) of action. GABA induced gastric relaxation, which was antagonized by the GABA A -receptor antagonist, bicuculline, potentiated by phaclofen, GABA B -receptor antagonist, but not affected by 1,2,5,6-Tetrahydropyridin-4-yl methylphosphinic acid hydrate (TPMPA), GABA C -receptor antagonist. Muscimol, GABA A -receptor agonist, mimicked GABA effects inducing relaxation, which was significantly re…

Baculovirus-mediated periadventitial gene transfer to rabbit carotid artery

2000

Recombinant Autographa californica multiple nuclear polyhedrosis viruses (AcMNPV) have recently been shown to transduce mammalian cells in vitro. Since baculoviruses offer many advantages over viruses currently used in gene therapy, we have tested them for in vivo gene transfer by constructing a baculovirus bearing a nuclear targeted beta-galactosidase marker gene (LacZ) under a CMV promoter. Both rabbit aortic smooth muscle cells (RAASMC) and human ECV-304 cells were susceptible to LacZ-baculovirus transduction. Transgene expression was evaluated in vivo by applying 1 x 10(9) p.f.u. of LacZ-baculoviruses or LacZ-adenoviruses in a silastic collar placed around rabbit carotid arteries in the…

Some approximation properties of ( p , q ) $(p,q)$ -Bernstein operators

2016

This paper is concerned with the $(p,q)$ -analog of Bernstein operators. It is proved that, when the function is convex, the $(p,q)$ -Bernstein operators are monotonic decreasing, as in the classical case. Also, some numerical examples based on Maple algorithms that verify these properties are considered. A global approximation theorem by means of the Ditzian-Totik modulus of smoothness and a Voronovskaja type theorem are proved.