Search results for "Constriction"
showing 10 items of 254 documents
Contribution of nitric oxide synthase isoforms to cholinergic vasodilation in murine retinal arterioles.
2013
Abstract Nitric oxide synthases (NOSs) are critically involved in regulation of ocular perfusion. However, the contribution of the individual NOS isoforms to vascular responses is unknown in the retina. Because some previous findings suggested an involvement of inducible nitric oxide synthase (iNOS) in the regulation of retinal vascular tone, a major goal of the present study was to examine the hypothesis that iNOS is involved in mediating cholinergic vasodilation responses of murine retinal arterioles. Another subject of this study was to test the contribution of the other two NOS isoforms, neuronal (nNOS) and endothelial NOS (eNOS), to cholinergic retinal arteriole responses. Expression o…
Antiasthmatic Effects of <i>Galphimia glauca</i>, Gallic Acid, and Related Compounds Prevent Allergen- and Platelet-Activating Factor-Ind…
1992
A methanolic extract from Galphimia glauca (320 mg/kg, orally) inhibited acute bronchial reactions to allergen (ovalbumin, 10 mg/ml) and platelet-activating factor (PAF, 1 microgram/ml) inhalation challenges, but not to histamine or acetylcholine in spontaneously breathing guinea pigs. Furthermore, the PAF-induced bronchial hyperreactivity was markedly reduced. Gallic acid and related compounds as well as the flavonoid, quercetin, were identified as active compounds. Gallic acid, methyl gallate and quercetin showed significant effects after a single oral dose of 45 mg/kg, tetragalloyl quinic acid after 5 mg/kg. Continuous treatment of the animals with one certain fraction (GG II, 3 days, 3 …
Changes in nasal air flow and school grades after rapid maxillary expansion in oral breathing children
2011
Objective: To analyse the changes in nasal air flow and school grades after rapid maxillary expansion (RME) in oral breathing children with maxillary constriction. Material and Methods: Forty-four oral breathing children (mean age 10.57 y) underwent orthodontic RME with a Hyrax screw. Forty-four age-matched children (mean age 10.64 y) with nasal physiological breathing and adequate transverse maxillary dimensions served as the control group. The maxillary widths, nasal air flow assessed via peak nasal inspiratory flow (PNIF), and school grades were recorded at baseline, and 6 months and one year following RME. Results: After RME, there were significant increases in all the maxillary widths …
Ceramide inhibits Kv currents and contributes to TP-receptor-induced vasoconstriction in rat and human pulmonary arteries
2011
et al.
Regulation of connexin gene expression during skeletal muscle regeneration in the adult rat
2009
In the adult skeletal muscle, various kinds of trauma promote proliferation of satellite cells that differentiate into myoblasts forming new myofibers or to repair the damaged one. The aim of present work was to perform a comparative spatial and temporal analysis of connexin (Cx) 37, Cx39, Cx40, Cx43, and Cx45 expression in the adult regenerating skeletal muscle in response to crush injury. Within 24 h from injury, Cx37 expression was upregulated in the endothelial cells of blood vessels, and, 5 days after injury, Cx37-expressing cells were found inside the area of lesion and formed clusters generating new blood vessels with endothelial cells expressing Cx37. Three days after injury, Cx39 m…
Effects of selective phosphodiesterase inhibitors on platelet-activating factor- and antigen-induced airway hyperreactivity, eosinophil accumulation,…
1996
There is currently interest in the potential use of selective inhibitors of cyclic nucleotide phosphodiesterases (PDE) in the treatment of asthma. In this study we examined the effects of three selective PDE inhibitors, milrinone (PDE III), rolipram (PDE IV) and zaprinast (PDE V), on the broncoconstriction produced by antigen and histamine, the airway hyperreactivity and microvascular leakage after aerosol exposure to platelet-activating factor (PAF) and antigen, and the antigen-induced eosinophil infiltration in guinea-pig lung. Inhaled rolipram (0.01-10 mg ml-1) inhibited dose dependently the bronchospasm produced by aerosol antigen (5 mg ml-1) an anaesthetised, ventilated guinea-pigs. Ro…
Lactoferricin B-derived peptides with inhibitory effects on ECE-dependent vasoconstriction
2010
Endothelin-converting enzyme (ECE), a key peptidase in the endothelin (ET) system, cleaves inactive big ET-1 to produce active ET-1, which binds to ET(A) receptors to exert its vasoconstrictor and pressor effects. ECE inhibition could be beneficial in the treatment of hypertension. In this study, a set of eight lactoferricin B (LfcinB)-derived peptides, previously characterized in our laboratory as angiotensin-converting enzyme (ACE) inhibitory peptides, was examined for their inhibitory effects on ECE. In vitro inhibitory effects on ECE activity were assessed using both the synthetic fluorogenic peptide substrate V (FPS V) and the natural substrate big ET-1. To study vasoactive effects, an…
First Evidence for a Crosstalk Between Mitochondrial and NADPH Oxidase-Derived Reactive Oxygen Species in Nitroglycerin-Triggered Vascular Dysfunction
2008
Chronic nitroglycerin treatment results in development of nitrate tolerance associated with endothelial dysfunction (ED). We sought to clarify how mitochondria- and NADPH oxidase (Nox)-derived reactive oxygen species (ROS) contribute to nitrate tolerance and nitroglycerin-induced ED. Nitrate tolerance was induced by nitroglycerin infusion in male Wistar rats (100 microg/h/4 day) and in C57/Bl6, p47(phox/) and gp91(phox/) mice (50 microg/h/4 day). Protein and mRNA expression of Nox subunits were unaltered by chronic nitroglycerin treatment. Oxidative stress was determined in vascular rings and mitochondrial fractions of nitroglycerin-treated animals by L-012 enhanced chemiluminescence, revea…
Diminished neurogenic femoral artery vasoconstrictor response in a Zucker obese rat model: differential regulation of NOS and COX derivatives.
2014
Objective: Peripheral arterial disease is one of the macrovascular complications of type 2 diabetes mellitus. This study addresses femoral artery regulation in a prediabetic model of obese Zucker rats (OZR) by examining cross-talk between endothelial and neural factors. Methods and Results: Arterial preparations from lean (LZR) and OZR were subjected to electrical field stimulation (EFS) on basal tone. Nitric oxide synthase (NOS) and cyclooxygenase (COX) isoform expression patterns were determined by immunohistochemical labelling and Western blotting. Results indicate significantly reduced noradrenergic contractions in preparations from OZR compared with those of LZR. Functional inhibition …
Effects of inhaled glaucine on pulmonary responses to antigen in sensitized guinea pigs.
2000
The alkaloid (S)-(+)-1,2,9,10-tetramethoxyaporphine (glaucine) is a phosphodiesterase 4 inhibitor with bronchodilator and anti-inflammatory activity in vitro. In this study, we examined the in vivo effects of glaucine on an animal model of asthma. In ovalbumin sensitized guinea pigs, inhaled glaucine (10 mg ml(-1), 3 min) inhibited the acute bronchoconstriction produced by aerosol antigen (antigen response was 256+/-42 and 95+/-14 cm H(2)O l(-1) s(-1) in control and glaucine-treated animals, respectively; P<0.05). Pretreatment with glaucine (10 mg ml(-1), 10 min inhalation, 30 min pre- and 3 h post-antigen exposure) markedly reduced airway hyperreactivity to histamine, eosinophil lung accum…