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Schl?ter Torsten - - 2010
AIMS: The present study was performed to investigate the contribution of NADPH oxidases (Nox) to superoxide formation in human renal proximal resistance arteries and to test whether superoxide formation contributes to acute vasoconstrictor responses and endothelium-dependent vasodilation in these vessels. METHODS AND RESULTS: Arcuate and proximal interlobular artery segments were ...
Syyong H T - - 2009
Marfan syndrome, a connective tissue disorder caused by mutations in FBN1 encoding fibrillin-1, results in life-threatening complications in the aorta, but little is known about its effects in resistance vasculature. Second-order mesenteric arteries from mice at 3, 6 and 10 months of age (n= 30) heterozygous for the Fbn1 allele ...
Lin Le-Jian - - 2009
This study was designed to test the hypothesis that a 28-day tail suspension (SUS) could induce hypertrophy and enhanced myogenic and vasoconstrictor reactivity in middle cerebral arteries (MCAs), whereas atrophy and decreased myogenic and vasoconstrictor responses in mesenteric third-order arterioles (MSAs). Also, in addition to the functional enhancement in MCAs, ...
Dogulu Fikret - - 2009
AIM: Endothelin-1 (ET-1) has been implicated in the pathophysiology of cerebral vasospasm. Chloride (Cl-) channels exist in vascular smooth muscle and activation of these channels leads to depolarization and contraction. The aim of the present study was to test the effect of 5-nitro-2-(3-phenylpropylamino)-benzoate (NPPB), a Cl- channel antagonist, on the ...
Rowell K O - - 2009
BACKGROUND: Testosterone is recognized to elicit vasodilatation in numerous vascular beds, however to date no study has investigated whether testosterone has this effect in the human pulmonary vasculature. AIM: To determine whether isolated human pulmonary arteries and veins dilate in response to testosterone and whether the response differs in relation ...
Mirkhani Hossein - - 2009
PURPOSE: Internal mammary artery (IMA) and saphenous vein (SV) are two most common vessels used in coronary artery bypass grafting (CABG). In the present study, the effect of levosimendan (a novel inotropic/vasodilator compound) and papaverine are compared, using IMA and SV obtained from CABG patients. METHODS: Unused segments of IMA ...
Din Sarah - - 2009
Genetic mutations in bone morphogenetic protein receptor 2 (BMPR2) have been shown to occur in patients with familial and idiopathic pulmonary arterial hypertension (PAH). However the interactions between ligands for this receptor and other mediators implicated in heritable PAH have not been investigated. This study examines the regulation of endothelin-1 ...
Cable David George - - 2009
BACKGROUND: Asymmetric dimethylarginine (ADMA), produced during protein metabolism, is an endogenous inhibitor of nitric oxide synthase, but little is known about its direct vasoactive properties in different arterial beds. MATERIAL/METHODS: Segments of canine coronary, renal, and femoral arteries were pretreated with increasing concentrations of ADMA, and endothelial function was evaluated ...
Yemisci Muge - - 2009
Here we show that ischemia induces sustained contraction of pericytes on microvessels in the intact mouse brain. Pericytes remain contracted despite successful reopening of the middle cerebral artery after 2 h of ischemia. Pericyte contraction causes capillary constriction and obstructs erythrocyte flow. Suppression of oxidative-nitrative stress relieves pericyte contraction, reduces ...
Owens Christopher D CD Division of Vascular and Endovascular Surgery, University of California San Francisco, San Francisco, CA 94143-0222, USA. - - 2009
As in arteries, venous endothelium modulates vessel homeostasis and tone. The effect of an arterialized environment on venous endothelial function remains poorly understood. In particular, regulation of saphenous vein graft (SVG) blood flow and lumen caliber remains undefined. We hypothesized that mature SVGs would exhibit endothelium-dependent, flow-mediated vasodilation (FMD). We ...
Disli Olcay Murat - - 2009
Radial artery (RA) vasospasm remains a potential cause of early graft failure after coronary artery bypass graft surgery, despite pretreatment with alpha-adrenergic or calcium channel blockers. Our aim was to investigate the mechanism of the vasorelaxant effects of Rho-kinase inhibitors (Y-27632 and fasudil) on the human RA. Segments were obtained ...
Meens Merlijn J P M T - - 2009
We tested the hypothesis that endothelin-1 (ET-1) modulates sensory-motor nervous arterial relaxation by prejunctional and postjunctional mechanisms. Isolated rat mesenteric resistance arteries were investigated with immunohistochemistry, wire-myography, and pharmacological tools. ET(A)- and ET(B)-receptors could be visualized on the endothelium and smooth muscle and on periarterial fibers containing calcitonin gene-related peptide ...
Chan Kayi Y - - 2009
Tegaserod, a 5-HT(4) receptor agonist, has been used to treat idiopathic constipation and constipation-predominant irritable bowel disease. It has recently been suggested that tegaserod has an affinity for 5-HT(1B) receptors, which mediate vasoconstriction. As some patients have experienced cardiac ischemia during treatment with tegaserod, we assessed contractions to tegaserod in ...
Zhang Jin - - 2009
Prolonged ouabain administration to normal rats causes sustained blood pressure (BP) elevation. This ouabain-induced hypertension (OH) has been attributed, in part, to the narrowing of third-order resistance arteries (approximately 320 microm internal diameter) as a result of collagen deposition in the artery media. Here we describe the structural and functional ...
Torrens Christopher - - 2009
The nutritional environment during development and even prior to conception may contribute to cardiovascular risk. In mature adult female sheep, we investigated the effect of preconceptional and periconceptional maternal nutritional restriction on the vascular reactivity of arteries from four vascular beds supplying the heart, thorax, kidney and hindlimb. Welsh Mountain ...
Villalba Nuria - - 2009
Erectile dysfunction frequently coexists with coronary artery disease and has been proposed as a potential marker for silent coronary artery disease in type 2 diabetes. In the present study, we comparatively assessed the structural and functional changes of both penile arteries (PAs) and coronary arteries (CAs) from a prediabetic animal ...
Pagán Rosa María - - 2009
The localisation and function of noradrenergic perivascular innervation of the radial artery were examined in a porcine model. Through immunohistochemical techniques, we explored the possible existence of dopamine beta-hydroxylase and choline-acetyltransferase in the nerve fibres supplying the radial artery. Arterial rings suspended in organ baths were used to isometrically record ...
Juntes Polona - - 2009
Ostreolysin (Oly), a cytolytic and cardiotoxic protein from the oyster mushroom (Pleurotus ostreatus), is lethal for mice with an LD(50) of 1170 microg/kg following intravenous application. Its cardiotoxicity is associated with hyperkalemia, which is probably a consequence of potassium released from the lysed cells. Moreover, sub-micromolar concentrations of Oly induce ...
Kristek F - - 2009
We demonstrate the effect of long-term nNOS inhibition with 7-nitroindazole (7NI) on the heart and conduit arteries. Ten weeks old Wistar rats were used: two groups of controls and rats receiving 7-NI (10 mg/kg b.w./day) for 6 weeks in drinking water. Blood pressure (BP) was measured by the plethysmographic method. ...
Gragasin Ferrante S - - 2009
Hypotension following administration of propofol, an anesthetic agent, is strongly predicted by advanced age and is partly due to direct vasodilation. We hypothesized that propofol increases nitric oxide (NO)-mediated vasodilation by enhancing its bioavailability in the aged adult vasculature, leading to greater vasodilation than in the young adult. Small mesenteric ...
Szolnoky Jeno - - 2009
OBJECTIVE: Radial arteries are increasingly used as grafts in coronary artery bypass surgery. The surgical preparation and intraoperative management of this conduit artery may affect its early and long-term patencies. We investigated the effects of the colloidal Biseko and 5% albumin solutions as well as the crystalloid physiological saline (0.9% ...
Wang Yan - - 2009
In this study, six major xanthones, isolated and identified from Halenia elliptica were investigated for their vasodilatory actions in isolated rat coronary artery. The xanthones, including 1-hydroxy-2,3,5-trimethoxy-xanthone (HM-1), 1-hydroxy-2,3,4,7-tetramethoxy-xanthone (HM-2), 1-hydroxy-2,3,4,5-tetramethoxy-xanthone (HM-3), 1,7-dihydroxy-2,3,4,5-tetramethoxy-xanthone (HM-4), 1,5-dihydroxy-2,3-dimethoxy-xanthone (HM-5) and 1,7-dihydroxy-2,3-dimethoxy-xanthone (HM-7) caused vasodilation in the coronary artery pre-contracted with 1 microM 5-hydroxytryptamine ...
Sennoun Nacira - - 2009
Recombinant human activated protein C (rhAPC) is one of the treatment panels for improving vascular dysfunction in septic patients. In a previous study, we reported that rhAPC treatment in rat endotoxemia improved vascular reactivity, although the mechanisms involved are still under debate. In the present study, we hypothesized that rhAPC ...
Mills Tracey A - - 2009
Control of vascular resistance and blood flow in the fetoplacental circulation is incompletely understood. Reactive oxygen species (ROS), physiological and pathophysiological regulators of vascular tone, are elevated in preeclampsia (PE), a disease of pregnancy characterized by increased fetoplacental vascular resistance. We tested the hypothesis that ROS modulate vascular reactivity in ...
Belin de Chantemèle Eric J - - 2009
OBJECTIVES: Chronic increases in blood flow induce remodeling associated with increases in diameter and endothelium-mediated dilation. Remodeling requires cell growth and migration, which may involve reactive oxygen species (ROS). Nevertheless, the role of ROS in flow-mediated remodeling in resistance arteries is not known. MATERIALS AND METHODS: Rat mesenteric resistance arteries ...
Long Yuan - - 2009
Caffeic acid phenethyl ester (CAPE) is a naturally occurring compound isolated from honeybee propolis whose cardiovascular properties remain uncertain. The purpose of this study was to investigate the possible mechanisms of CAPE-induced vasorelaxation in porcine coronary artery rings. It was found that both the quiescent and precontracted coronary artery ring ...
Bocquet Arnaud - - 2009
This study evaluated the effects of two PAR1 antagonists on vessels contracted by SFLLR. ER 121958 antagonized the SFLLR-induced contraction on rat denuded superior mesenteric artery and pig coronary artery in a non-competitive manner (IC(50) values were 22 [7.5-43.6] nM and 2.9 [2.09-4.02] nM, respectively). F 16618 inhibited the SFLLR-induced ...
Zhang Fan F Department of Pharmacology and Toxicology, Medical College of Virginia, Virginia Commonwealth University, 410 N 12th, Richmond, VA 23298, - - 2009
Cathepsin L is a cysteine protease that can generate endogenous endostatin in vascular and epithelial basement membranes and importantly participates in a variety of pathophysiological processes. The present study was designed to determine whether this cathepsin L-derived endogenous endostatin alters endothelium-dependent vasodilator responses in coronary arteries via NAD(P)H oxidase activation. ...
Andrews Karen L - - 2009
Nitroxyl (HNO) is emerging as an important regulator of vascular tone as it is potentially produced endogenously and dilates conduit and resistance arteries. This study investigates the contribution of endogenous HNO to endothelium-dependent relaxation and hyperpolarization in resistance arteries. Rat and mouse mesenteric arteries were mounted in small vessel myographs ...
Hilgers R H P - - 2009
We tested the hypothesis that activated arterial smooth muscle (ASM) stimulates endothelial vasomotor influences via gap junctions and that the significance of this myoendothelial coupling increases with decreasing arterial diameter. From WKY rats, first-, second-, third- and fourth-order branches of the superior mesenteric artery (MA1, MA2, MA3 and MA4 respectively) ...
Deka Dilip K - - 2009
In the present study, the mechanism of relaxant response of nitric oxide precursor, L-arginine, was investigated in goat isolated coronary artery. L-arginine (1 mM) reversed the U-46619 (1 microM)-induced contraction both in endothelium-intact and endothelium-denuded arterial ring preparations. L-arginine analogues, L-NAME, L-NNA and L-NMMA and the guanylyl cyclase inhibitor, methylene ...
Atalik K E - - 2009
The effects of cooling (to 28 degrees C) on the vasodilation induced by diazoxide (10(-9)-3 x 10(-4) M) on carbachol-pre-contracted calf cardiac vein and coronary artery and the role of nitric oxide in these effects were analyzed. Diazoxide produced concentration-dependent relaxation of calf cardiac vein and coronary artery rings pre-contracted ...
Pendyala Lakshmana K LK Saint Joseph's Translational Research Institute/Saint Joseph's Hospital of Atlanta, Atlanta, Georgia 30342, - - 2009
We sought to evaluate coronary epicardial and intramyocardial resistance, arterial vasomotor function, local inflammatory reaction, and superoxide anion (O(2)(.-)) production after overlapping paclitaxel-eluting stent (PES) implantation in a porcine model. PES implantation has been shown to elicit coronary vasomotor dysfunction. However, underlying mechanisms remain largely unknown. Nine pigs received overlapping ...
Nguyen Hao G HG Department of Cardiothoracic Surgery, Boston Medical Center, Boston, Massachusetts, - - 2009
Arterial grafts have patency rates superior to venous grafts in patients undergoing coronary bypass grafting surgery. Natriuretic peptides play a major role in vascular homeostasis. We hypothesized that natriuretic peptides might have different effects on arterial and venous conduits. The relaxation responses and tissue levels of cyclic guanosine monophosphate (cGMP) ...
Mayhan William G WG Department of Cellular and Integrative Physiology, 985850 Nebraska Medical Center, Omaha, NE 68198-5850, USA. - - 2009
Our goals were to determine whether acute exposure to nicotine alters nitric oxide synthase (NOS)-dependent responses of the basilar artery and to identify a potential role for activation of NAD(P)H oxidase in nicotine-induced impairment in NOS-dependent responses of the basilar artery. We measured in vivo diameter of the basilar artery ...
Teoh Hwee - - 2009
OBJECTIVE: To explore the effects of different estrogens on vascular function, we compared the vasorelaxant effects of 17beta-estradiol, 17alpha-estradiol, estrone, and the synthetic estrogen diethylstilbestrol (DES) on porcine coronary arterial segments. DESIGN: Porcine coronary arterial rings were contracted with the stable thromboxane A2 analogue U46619 (3 x 10(-8) M), and ...
Tirapelli Carlos R - - 2009
The carotid artery has a pivotal role in the body since it supplies the head and neck with oxygenated blood. Alterations in the functional and structural integrity of these vessels can decrease blood flow to the brain. For this reason, it is important to understand how the carotid artery responds ...
Stevanovic Darco - - 2009
Hydroperoxide-induced oxidative stress is assumed to be involved in vasospasm of cerebral arteries after subarachnoid hemorrhage. In order to study underlying mechanisms the effects of H2O2 and tert butylhydroperoxide on contractile functions as well as on free radical production of anterior cerebral artery from pig were investigated. The hydroperoxides increased ...
Maharaj Chrisen H - - 2009
OBJECTIVES: Sildenafil citrate, a specific phosphodiesterase-5 inhibitor, is increasingly used for pulmonary hypertension in pregnancy. Sildenafil is also emerging as a potential candidate for the treatment of intra-uterine growth retardation and for premature labor. Its effects in the feto-placental circulation are not known. Our objectives were to determine whether phosphodiesterase-5 ...
Matsuda Nilce Mitiko - - 2009
Segments of the canine internal mammary artery (35 mm in length) were suspended in vitro in an organ chamber containing physiological salt solution (95% O2/5% CO2, pH = 7.4, 37 degrees C). Segments were individually cannulated and perfused at 5 ml/minute using a roller pump. Vasorelaxant activity of the effluent ...
Lakshminrusimha Satyan S Department of Pediatrics, University of Buffalo, Buffalo, NY, USA. - - 2009
Prostacyclin is a pulmonary vasodilator and is produced by prostacyclin synthase and stimulates adenylate cyclase (AC) via the prostacyclin receptor (IP) to produce cAMP. Forskolin is a direct stimulant of AC. Phosphodiesterase 3 hydrolyzes cAMP and is inhibited by milrinone. To characterize the prostacyclin-AC-cAMP pathway in the ovine ductal ligation ...
Dhadwal Ajay K AK Molecular Surgeon Research Center, Division of Vascular Surgery and Endovascular Therapy, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX 77030, - - 2009
Highly active antiretroviral therapy (HAART) including HIV protease inhibitor ritonavir may be associated with the clinical complications including accelerated atherosclerosis and pulmonary artery hypertension. The objective of this study was to determine whether capsaicin, a major ingredient of hot pepper with antioxidative property, could effectively inhibit ritonavir-induced oxidative injury in ...
Aggarwal Nitin T - - 2009
15-Lipoxygenase (15-LO-1) metabolizes arachidonic acid (AA) to 11,12,15-trihydroxyeicosatrienoic acids (THETAs) and 15-hydroxy-11,12-epoxyeicosatrienoic acids (HEETA) that dilate rabbit arteries. Increased endothelial 15-LO-1 expression enhances arterial relaxations to agonists. We tested the effect of hypoxia on 15-LO-1 expression, THETA and HEETA synthesis, and relaxations in rabbit arteries. The incubation of rabbit aortic ...
Shi Jian - - 2009
The right gastroepiploic artery (GEA) is frequently used as another in situ artery, other than the internal thoracic artery (ITA) in coronary artery bypass grafting (CABG). Skeletonizing the graft with an ultrasonic scalpel is now regarded as a useful technique; however, this technique may damage the endothelial function during harvesting ...
Zhang Ran - - 2009
Previous studies have demonstrated activation of the local renin-angiotensin system in hindlimb unweighting (HU) rat vasculature. The present study intended to identify the effects of blockade of angiotensin II (ANG II) type 1 (AT(1)) receptors with losartan on vascular reactivity, nitric oxide synthase (NOS) expression, and superoxide anion (O(2)(*-)) levels ...
Wang Yutang - - 2009
Erythrocyte-derived depressing factor (EDDF) shows significant protective effects on blood vessels from hypertensive rats, by regulating vascular reactivity, calcium homeostasis, DNA synthesis, and cell cycle progression in vascular smooth muscles (VSMCs). Arteries from hypertensive and aging people have high levels of accumulated calcium. However, in the life span of experimental ...
Oualha M - - 2008
Background: It has recently been shown that systemic endothelial dysfunction is associated with airflow limitation in COPD. We conducted this ex vivo study to assess whether endothelial dysfunction of pulmonary arteries of former smokers was associated with modifications of airway functions. Methods: Pharmacological experiments were conducted on arterial and bronchial ...
Hughes Jennifer M - - 2009
Occupational exposure to hand-operated vibrating tools causes a spectrum of pathological changes in the vascular, neurological, and musculoskeletal systems described as the hand-arm vibration syndrome (HAVS). Experiments were performed to determine the effects of acute vibration on the function of digital arteries. Rats paws were exposed to a vibrating platform ...
Farah Omar R - - 2009
The factors controlling the pulmonary vascular resistance under physiological conditions are poorly understood. We have previously reported on an apparent cross talk between the airway and adjacent pulmonary arterial bed where a factor likely derived from the bronchial epithelial cells reduced the magnitude of agonist-stimulated force in the vascular smooth ...
Wang Xinwen - - 2008
The objective of this study was to determine the effects and mechanisms of serum amyloid A (SAA) on coronary endothelial function. Porcine coronary arteries and human coronary arterial endothelial cells (HCAECs) were treated with SAA (0, 1, 10, or 25 microg/ml). Vasomotor reactivity was studied using a myograph tension system. ...
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