Search Results
Results 301 - 350 of 2918
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Yetkin Ertan - - 2007
BACKGROUND: It has been known that in a migraine attack intracranial and extracranial arteries on the headache side dilate and when the migraine attack has subsided, the intracranial arteries show segmental narrowing. We hypothesized that patients with migraine had an underlying systemic vasomotion abnormality and there might be an increased ...
Yugar-Toledo Juan Carlos - - 2007
The nitric oxide/cyclic-guanosine 3',5'-monophosphate signaling cascade plays an essential role in cardiovascular homeostasis but its involvement in the pathophysiology of refractory hypertension is unclear. The acute vasodilatory effect of a single oral dose of a phosphodiesterase-5 inhibitor (sildenafil citrate) on the brachial artery dilatation was evaluated in 25 normal healthy ...
Neidhold S - - 2007
Adrenoceptors can associate with cardiac caveolae. To investigate the function of vascular caveolae, adrenoceptor-mediated effects were compared in the saphenous artery of caveolin-1 knockout (cav-1KO) and wild-type (WT) mice. Electronmicroscopy was used to detect caveolae. Real-Time quantitative PCR was used for adrenoceptor subtypes. Catecholamine-evoked contractions and relaxations were studied in ...
Anaid Shahbazian - - 2007
The endothelium and its interaction with smooth muscle play a central role in the local control of the pulmonary vasculature, and endothelial dysfunction is thought to contribute to pulmonary hypertension and chronic obstructive pulmonary disease. Vasoactive intestinal peptide (VIP), a 28-amino acid neuropeptide, relaxes the rat pulmonary artery, but there ...
Tummala Saigiridhar - - 2007
We have previously reported that organ cultured coronary arteries from market-age pigs (6-9 months of age) exhibit an enhanced contraction to the atherosclerotic-associated peptide, endothelin-1 (ET-1). The objective of this study was to investigate the interaction of 17beta-estradiol with ET-1 in organ cultured coronary arteries from older female pigs (3-4 ...
Karadas Baris - - 2007
Alterations in vascular responses to beta-adrenoceptor agonists in normotensive pregnancy and pre-eclampsia are not fully understood. Thus, we studied changes in vasodilator responses to beta(2)-adrenoceptor agonist formoterol and beta(3)-adrenoceptor agonist BRL 37344 on umbilical arteries isolated from normotensive (n=12) and pre-eclamptic (n=12) pregnant women. Changes in the relaxant effect of ...
Konduri Girija G - - 2007
Persistent pulmonary hypertension of newborn (PPHN) is associated with decreased NO release and impaired pulmonary vasodilation. We investigated the hypothesis that increased superoxide (O(2)(*-)) release by an uncoupled endothelial nitric oxide synthase (eNOS) contributes to impaired pulmonary vasodilation in PPHN. We investigated the response of isolated pulmonary arteries to the ...
Tenorio-Lopez Fermin Alejandro - - 2006
Viscum album L. aqueous extract, on the Langendorff isolated and perfused heart model, decreases coronary vascular resistance, when compared to control group (36.00 +/- 2.00 vs. 15.80 +/- 1.96 dyn s cm-5). Our data support the fact that this mechanism involves NOS-2 and NOS-3 overexpression (4.65 and 7.89 times over ...
Wei Wei - - 2007
OBJECTIVES: Due to potential therapeutic value of vascular endothelial growth factor (VEGF) in coronary artery disease, the effect and mechanism of VEGF in human arteries used as coronary bypass grafts become important but not fully understood. VEGF-mediated endothelial regulation in vasorelaxation was studied in internal mammary artery (IMA) and radial ...
Mead Emma J - - 2007
The G protein-coupled receptor GPR54 (also designated KISS1) is activated by cleavage products of the KiSS1 protein, the kisspeptins (KP), to act as a molecular switch for puberty. Additionally, KP are potent inhibitors of tumor metastasis and play a role in placentation, both processes involving angiogenesis. Our aim was to ...
O'Sullivan S E - - 2006
The important role of nitric oxide (NO) in the regulation of vascular tone has been well studied. By contrast, the vascular significance of another gaseous mediator, hydrogen sulphide (H2S), is still poorly understood. A study published in this issue of the British Journal of Pharmacology now provides evidence that in ...
Erbs Sandra - - 2006
OBJECTIVES: Polymorphisms of endothelial nitric oxide synthase (eNOS) gene in the promoter (T-786C) and exon 7 (G894T) have been suggested to attenuate endothelial function. As it is unknown whether these polymorphisms, on top of classical risk factors, further deteriorate endothelium-dependent vasomotion, we aimed to elucidate the impact of both polymorphisms ...
Zhou Wei - - 2006
Homocysteine is an independent risk factor for atherosclerosis. The objective of this study was to investigate whether ginkgolide A (GA), a major constituent of Ginkgo biloba, could block homocysteine-induced endothelial dysfunction in porcine coronary arteries. Porcine coronary artery rings were assigned to six treatment groups: control; homocysteine (50 micromol/L); low-dose ...
Conklin D J - - 2006
Increased risk of vasospasm, a spontaneous hyperconstriction, is associated with atherosclerosis, cigarette smoking, and hypertension-all conditions involving oxidative stress, lipid peroxidation, and inflammation. To test the role of the lipid peroxidation- and inflammation-derived aldehyde, acrolein, in human vasospasm, we developed an ex vivo model using human coronary artery bypass graft ...
Aubin Marie-Claude - - 2007
The present study was designed to compare alterations of endothelium-dependent vasorelaxation in coronary epicardial arteries and subendocardial arterioles occurring in left ventricular hypertrophy (LVH) secondary to 60 days of aortic banding in a porcine model. Development of LVH was documented by echocardiogram and the endothelial function of subendocardial and epicardial ...
Otsuki Takeshi - - 2007
Arterial stiffness is higher in strength-trained humans and lower in endurance-trained humans. However, the mechanisms underlying these different adaptations are unclear. Vascular endothelium-derived factors, such as endothelin-1 (ET-1) and nitric oxide (NO), play an important role in the regulation of vascular tonus. We hypothesized that endogenous ET-1 and NO participate ...
Sánchez Ana - - 2006
To analyze the cerebrovascular effects of ischemia-reperfusion, cerebrovascular reactivity to ADP was studied after inducing 60-min occlusion followed by 60-min reperfusion of the left middle cerebral artery (MCA) in anesthetized goats. In 12 goats, at the end of reperfusion, left MCA resistance was decreased by 19%, and reactive hyperemia to ...
Bohr, David F.
The current study was undertaken to assess species and regional variations in the relaxation of vascular smooth muscle in response to potassium and in the ouabain sensitivity of this relaxation. The effect of species variation was investigated through the use of tail arteries from rats, dogs, cats, monkeys, and pigs; ...
Moroe Hiroko - - 2006
The present study was undertaken to investigate and compare the vascular function in carotid arteries isolated from normal short-term hypercholesterolemic rabbits. Rabbits were fed normal or 0.5% cholesterol chow for 5 weeks. The tension of isolated carotid artery rings was measured isometrically. Serum lipid levels were measured and morphometric analysis ...
Hammerer-Lercher Angelika - - 2006
In the present study, we investigated the vasodilator properties of A-type, B-type and C-type natriuretic peptides (ANP, BNP and CNP respectively) and the NO (nitric oxide) donor sin-1 (3-morpholino-sydnonimine) in human by-pass grafts. In contrast with previous studies, the same vessel was used to demonstrate a direct link between cGMP ...
Matsumoto Kazuhisa - - 2006
OBJECTIVE: There are few data available on the effect of ultrasonic skeletonization with the harmonic scalpel on internal thoracic artery (ITA) and gastroepiploic artery (GEA) vessel function. METHODS: Rings of segments of the skeletonized ITA, pedicled ITA, skeletonized GEA, and pedicled GEA were studied. Arterial segments were treated with high ...
Pataricza János - - 2006
Levosimendan is a novel inodilator drug developed for the treatment of heart failure. The possible vasodilating property of the drug in human coronary artery bypass grafts was investigated. Isometric tensions of the left internal thoracic artery (LITA, n = 8) as well as the proximal and distal segments of the ...
Kretz Martin - - 2006
We previously reported that angiotensin II (AngII)-induced vasoconstriction involves activation of cyclooxygenase (COX) in murine aorta and carotid artery. The aim of this study was to investigate the roles of early aging and COX in AngII-induced vasoconstriction in different vascular beds. Aortic, carotid, renal, and femoral artery rings of 19- ...
Iida Kiyoshi - - 2006
OBJECTIVES: We evaluated the potential vasodilator effects of transcutaneous low-frequency ultrasound (US) in human brachial arteries. BACKGROUND: Recent data show that transthoracic low-frequency US energy results in canine coronary artery vasodilation. METHODS: Brachial artery diameters were measured before and after low-frequency US (29 kHz, 1.4 W/cm2) exposure using US imaging ...
Kanki-Horimoto Sachiko - - 2006
BACKGROUND: Endothelial dysfunction is known to exaggerate coronary artery disease, sometimes leading to irreversible myocardial damage. In such cases, repetitive coronary revascularization including coronary artery bypass grafting is needed, which may cause a shortage of graft conduits. On the other hand, endothelial nitric oxide synthase (eNOS) is an attractive target ...
Wareing Mark - - 2006
OBJECTIVES: In pre-eclampsia (PE), endothelium-dependent function of myometrial small arteries is markedly attenuated. The residual PE response is wholly NO mediated. We have previously demonstrated that PDE5 inhibition can improve endothelial function in myometrial small arteries from women with PE. We aimed to assess whether the effect of PDE5 inhibition ...
Busija David W - - 2006
Insulin resistance (IR) has adverse effects on the reactivity of arteries and arterioles and promotes arterial hypertension and vascular occlusive diseases. Altered reactivity of resistance vessels occurs at both the endothelium and smooth-muscle levels. One major mechanism of vascular dysfunction with IR involves the augmented generation, availability, and/or actions of ...
Mullick Adam E - - 2006
We have reported that hyperhomocysteinemia (HHcy) evoked by folate depletion increases arterial permeability and stiffness in rats and that low folate without HHcy increases arterial permeability in mice. In this study, we hypothesized that HHcy independently increases arterial permeability and stiffness in mice. C57BL/6J mice that received rodent chow and ...
Sato Naoki - - 2006
BACKGROUND: Experimental study has shown that blunted arterial baroreflex function markedly attenuated inotropic responses to a phosphodiesterase inhibitor (PDEI) even in normal hearts. However, whether arterial baroreflex function is related to the inotropic responsiveness to a PDEI has not been clarified in human heart failure (HF). HYPOTHESIS: The goal of ...
Widmer Corinne C - - 2006
Although endothelin (ET)-1 is one of the strongest known vasoconstrictors in most species, we and others have previously found that it is only weakly effective in the mouse aorta. The aim of this study was to further investigate vasoactive effects of ET-1 in vascular beds generally known to be particularly ...
Arshad Muhammad - - 2006
BACKGROUND: The internal mammary artery (IMA) and the radial artery (RA) are routinely used in coronary artery bypass grafting. However, RA grafts have a higher incidence of postoperative vasospasm and comparatively poor patency rates. The present study was undertaken to investigate the signaling pathways mediating contraction and relaxation in the ...
Wang M - - 2006
Acetylcholine (ACh) induces nasal congestion at low doses but decongestion at high doses. The current study investigated the vascular mechanisms underlying this biphasic nasal airway response in dogs. Collecting and outflow veins from anterior and posterior nasal venous systems and the septal mucosa (containing sinusoidal venous plexuses) were isolated. The ...
Knock Greg A - - 2006
We examined the effects of dietary soy on the contributions of endothelium-derived hyperpolarising factor (EDHF), nitric oxide (NO), and oxidative stress to vascular tone in isolated aortic rings and small mesenteric and pulmonary arteries in vitro. Male Wistar rats were either continuously fed a soy-deficient diet (SD) or switched from ...
Fresquet Fleur - - 2006
1. This study investigates the role of nitric oxide (NO) and reactive oxygen species (ROS) on endothelial function of pulmonary arteries in a mice model of hypoxia-induced pulmonary hypertension. 2. In pulmonary arteries from control mice, the NO-synthase inhibitor Nomega-nitro-L-arginine methyl ester (L-NAME) potentiated contraction to prostaglandin F2alpha (PGF2alpha) and ...
Jacobs Elizabeth R - - 2006
The cytochrome P-450 metabolite 20-HETE induces calcium-, endothelial-, and nitric oxide (NO)-dependent relaxation of bovine pulmonary arteries (PA). VEGF is an NO-dependent dilator of systemic arteries and plays a key role in maintaining the integrity of the pulmonary vasculature. We tested the effect of VEGF on PA diameter and tone ...
Yada Toyotaka - - 2006
We have recently demonstrated that endogenous H2O2 plays an important role in coronary autoregulation in vivo. However, the role of H2O2 during coronary ischemia-reperfusion (I/R) injury remains to be examined. In this study, we examined whether endogenous H2O2 also plays a protective role in coronary I/R injury in dogs in ...
Nandi Manasi M Division of Medicine, British Heart Foundation Labortories, The Rayne Institute, University College London, London, WC1E 6JJ, United Kingdom. - - 2006
Nitric oxide (NO) plays an important role in lowering pulmonary vascular resistance after birth. However, in persistent pulmonary hypertension of the newborn (PPHN) NO-mediated dilation is dysfunctional. GTP-cyclohydrolase 1 (GTP-CH1) is the rate-limiting enzyme for the biosynthesis of 6R-L-erythro-5,6,7,8-tetrahydrobiopterin (BH4) an essential cofactor for nitric oxide synthase (NOS) activity. Suboptimal ...
Gursoy Sinan - - 2007
OBJECTIVE: Intravenous anesthetics are often used for anesthesia, sedation, and analgesia in the intraoperative and postoperative periods of coronary artery bypass graft (CABG) surgery. This study was designed to investigate the direct effects of intravenous anesthetics on the human radial artery (RA). DESIGN: In vitro, prospective with repeated measures. SETTING: ...
Ohata Shuzo - - 2006
1. Previous clinical studies with prostaglandin I(2) (PGI(2)) analogue beraprost sodium suggested the potential effects on protection of cardiovascular events in patients with peripheral artery disease. Although the mechanism is not well known, experimental studies have shown protective effects of endothelial cells. This study was designed to examine the effects ...
Barber Melissa N - - 2006
OBJECTIVE: Neutral endopeptidase (NEP, EC 3.4.24.11) metabolises endogenous vasoactive peptides that may protect against atherogenesis. Since NEP is found in the adventitia of arteries, we investigated the anti-atherogenic effects of chronic adventitial NEP inhibition. METHODS: Intimal hyperplasia of rabbit carotid arteries was induced by placement of soft, non-occlusive, peri-arterial silastic ...
Shi Yi - - 2006
Individual vascular beds exhibit differences in vascular reactivity. The present study investigates the effects of streptozotocin-induced type I diabetes on endothelium-dependent responses of rat carotid, femoral, and mesenteric arteries. Rings with and without endothelium, suspended in organ chambers for isometric tension recording, were contracted with phenylephrine and exposed to increasing ...
McNeish Alister J - - 2006
BACKGROUND AND PURPOSE: Endothelium-derived hyperpolarizing factor responses in the rat middle cerebral artery are blocked by inhibiting IKCa channels alone, contrasting with peripheral vessels where block of both IKCa and SKCa is required. As the contribution of IKCa and SKCa to endothelium-dependent hyperpolarization differs in peripheral arteries, depending on the ...
Tasatargil Arda - - 2007
This study was aimed to examine the effects of homocysteine (Hcy) on vascular responsiveness of guinea-pig isolated pulmonary arteries and to investigate possible underlying mechanisms. In order to evaluate vascular reactivity, isometric tension studies were performed in response to potassium chloride (KCl), phenylephrine (Phe), acetylcholine (ACh), and sodium nitroprusside (SNP). ...
Young Joseph B - - 2007
There are few instruments specifically designed to measure circumferential force generated by ring segments of arteries in vitro. Typical limitations of some existing machines include poor isometry, large organ bath volume or difficult sample mounting. The authors designed, built and tested a device for isometric tension recording of force developed ...
Gazzieri David - - 2006
OBJECTIVES: Consumption of alcoholic beverages reduces the risk of coronary artery disease (CAD), and epidemiological studies have shown that ethanol per se is protective. However, the mechanism by which ethanol exerts protection is not fully known. Ethanol can stimulate neuropeptide-containing primary sensory neurons via the activation of transient receptor potential ...
Ohwada Takayuki - - 2006
We investigated the difference in vascular responses and remodeling between coronary and iliac arteries after repeated endothelial denudation. Endothelial denudation of the left anterior descending coronary artery (LAD) and the right common iliac artery (RIA) was repeated 4 times twice a month using a Fogarty catheter in 21 pigs. Vascular ...
Gursoy S - - 2006
BACKGROUND AND OBJECTIVE: Arterial grafts are prone to vasospasm. Opioid analgesics are commonly used in the perioperative course of cardiac surgical procedures. Therefore, we investigated the direct effects of morphine, meperidine, fentanyl and remifentanil on the human radial artery. METHODS: Radial artery segments, obtained from 20 patients, were precontracted with ...
Kato Kenichi - - 2006
We investigated the difference in the characteristics of endothelin-1 (ET-1)-induced contraction and the responses of intracellular Ca(2+) concentration ([Ca(2+)](i)) between rat small pulmonary artery and renal artery. ET-1 (30 nM) failed to elicit any contraction in renal arteries pretreated with 3 microM BQ-123, an ETA blocker. However, in the pulmonary ...
Hanna Salma Toma - - 2006
Smoking is a leading cause of cardiovascular disease, hypertension, myocardial infarction, and stroke. Nicotine is one of the components of cigarette smoke. Nicotine effects on the cardiovascular system reflect the activity of the nicotine receptors centrally and on peripheral autonomic ganglia. It has been found that cigarette smoke extract-induced contraction ...
Tsai Ben M - - 2006
BACKGROUND: Endotoxemia causes paradoxical effects on the systemic and pulmonary vasculature, resulting in systemic hypotension and increased pulmonary artery pressure. The local production of inflammatory mediators may have important effects on vascular tissue function. The purpose of this study was to delineate differences in function and the expression of tissue ...
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