Search results for " oxide"
showing 10 items of 2491 documents
Prevention of Atherosclerosis by Interference with the Vascular Nitric Oxide System
2009
Nitric oxide (NO) produced by endothelial NO synthase (eNOS) represents an anti-atherosclerotic principle. NO bioavailability is decreased in atherosclerosis due to increased NO inactivation by reactive oxygen species and reduced NO synthesis. Various types of vascular pathophysiology are associated with oxidative stress, with NADPH oxidases as the major source of reactive oxygen species. These inactivate NO. Also, oxidative stress is likely to be the main cause for oxidation of the essential NOS cofactor, tetrahydrobiopterin (BH(4)). A lack of BH(4) leads to eNOS uncoupling (i.e., uncoupling of oxygen reduction from NO synthesis in eNOS). Based on these pathomechanisms, the therapeutic pot…
Endothelial modulation of 5-hydroxytryptamine-induced contraction in goat cerebral arteries.
1993
Abstract 1. 1. In isolated goat middle cerebral artery segments, 5-hydroxytryptamine (5-HT, 10 −8 −3 × 10 −5 M) caused concentration-dependent contractions, with EC 50 = 2.1 (1.9−2.5) × 10 −7 M and E max = 60 ± 2% of 50 mM KCl-induced contraction. 2. 2. Mechanical removal of endothelium significantly increased the E max (91 ± 8%) and did not change the EC 50 value of 5-HT-elicited contractions. 3. 3. Incubation of unrubbed arteries with the irreversible inhibitor of EDRF, gossypol (10 −5 M), significantly increased the contractile response to 5-HT ( E max = 77 ± 4%). 4. 4. Incubation of unrubbed arteries with the competitive inhibitor of the NO synthesis, N G -nitro - l -arginine (L-NOARG) …
Measurement of exhaled nitric oxide: comparison of 3 different analyzers
2018
Exhaled nitric oxide (FeNO) is used as a surrogate marker to monitor airway inflammation. Aim of this study was to compare the new FeNO analyzer Vivatmo pro from Bosch (BV) with the Niox Vero from Circassia (CN) and the CLD from Ecomedics (EC). In 106 asthma patients (median age 54 years (range 20-87), 60 % female, median ACT of 16, 85 % on inhaled corticosteroids (mean 1300 μg BDP), 36 % on therapy with biologics) 2 FeNO measurements per patient and per device were performed using each analyzer in a random sequence according to the ATS / ERS guidelines. Additionally, the success rate to achieve a valid NO value was evaluated. 70 % of the patients had FeNO values In conclusion, for the rang…
Combined sub-optimal doses of Rosuvastatin and Bexarotene impairs angiotensin II-induced arterial mononuclear cell adhesion through inhibition of Nox…
2015
Aim: Mononuclear cell (MC) infiltration into the arterial subendothelium is a key event in atherogenesis. Rosuvastatin (Rosu) and bexarotene (Bex) exert anti-inflammatory activity, but serious dose-related adverse effects have emerged. The need for safer and effective strategies to prevent and treat atherosclerosis led us to test the effect of combined use of both drugs on angiotensin II (Ang-II)-induced arterial MC recruitment. Results: Vehicle, Rosu (10–30 nM), Bex (0.3–1 μM), or a combination of both were administered to human umbilical arterial endothelial cells (HUAECs) 20 h before stimulation with 1 μM Ang-II (4 h). Surprisingly, a combination of Rosu (10 nM)+Bex (0.3 μM), which did n…
Late Breaking Abstract - Efficacy of CSJ117 on allergen-induced asthmatic responses in mild atopic asthma patients
2020
Introduction: CSJ117 is a potent neutralizing antibody fragment against human Thymic stromal lymphopoietin (TSLP), formulated as a PulmoSol™ engineered powder in hard capsules for delivery to the lungs via dry powder inhaler. Methods: In this double-blind, placebo-controlled study, 28 mild, atopic asthmatics meeting elibility criteria were randomized to receive 4mg CSJ117 (n = 15) or placebo (n = 13) inhaled daily for 12 weeks. Allergen inhalation challenge (AIC) was conducted at screening, day 42 and day 84. The primary efficacy variable was the late asthmatic response (LAR), measured 3 to 7 hours after AIC at day 84. Other outcomes included the early asthmatic response (EAR) measured with…
Vasoactive intestinal peptide stimulation of cyclic guanosine monophosphate formation: further evidence for a role of nitric oxide synthase and cytos…
1993
In the rat pineal gland vasoactive intestinal peptide (VIP) and beta-adrenergic agonists stimulate cyclic guanosine monophosphate (cGMP) formation and their action is amplified by alpha 1-adrenergic agonists. Since beta-adrenergic stimulation of cGMP is suggested to involve activation of nitric oxide (NO) synthase and NO-mediated activation of cytosolic guanylate cyclase (GC), we investigated the effects of the NO synthase inhibitor N-monomethyl-L-arginine (L-NMMA) and of the cytosolic GC inhibitor methylene blue (MB) on VIP receptor-stimulated cGMP formation. Both L-NMMA and MB depressed VIP-induced cGMP formation as well as alpha 1-adrenergic potentiation of VIP-stimulated cGMP formation …
Is oxidative stress a therapeutic target in cardiovascular disease?
2010
An abnormal production of reactive oxygen species (ROS) and the subsequent decrease in vascular bioavailability of nitric oxide (NO) have long been proposed to be the common pathogenetic mechanism of the endothelial dysfunction, resulting from diverse cardiovascular risk factors such as hypercholesterolaemia, diabetes mellitus, chronic smoking, metabolic syndrome, and hypertension. Superoxide produced by the nicotinamide dinucleotide phosphate (NADPH) oxidase, mitochondrial sources, or the xanthine oxidase may react with NO, thereby resulting in excessive formation of peroxynitrite, a reactive nitrogen species that has been demonstrated to accelerate the atherosclerotic process by causing d…
Complete blockade of the vasorelaxant effects of angiotensin-(1-7) and bradykinin in murine microvessels by antagonists of the receptor Mas
2013
Key points • Two distinct angiotensin-(1–7) [Ang-(1–7)] receptor blockers, A779 and d-Pro-Ang-(1–7), can completely prevent Ang-(1–7)-induced vasorelaxation. • Genetic deficiency of Mas completely prevents vascular responses to Ang-(1–7). • Genetic deficiency of Mas completely prevents vascular responses to other NO-dependent vasorelaxants (bradykinin). • Mas plays a key role in NO-mediated vasodilatation by modulating vasorelaxant-mediated phosphorylation of endothelial nitric oxide synthase in endothelial cells. Abstract The heptapeptide angiotensin-(1–7) is a biologically active metabolite of angiotensin II, the predominant peptide of the renin–angiotensin system. Recently, we have show…
Increased synthesis of nitric oxide in rat brain cortex due to halogenated volatile anesthetics confirmed by EPR spectroscopy
2002
Background: Halogenated volatile anesthetics (HVAs) are considered to be inhibitors of nitric oxide synthase (NOS). On other hand, NO mediates the vasodilation produced by HVAs. Thus, both increase and decrease of NO concentration in brain tissues are possible during anesthesia. Previously, we have observed an increase of NO content in rat brain cortex under halothane anesthesia. The goal of this study was to determine whether the observed phenomenon was general for this anesthetic group, if it was specific for brain cortex, and if the NO increase was due changes in NOS activity. Methods: NO scavengers were injected to adult rats 30 min prior to anesthesia. Rats were anesthetized by inhalat…
The Relationship between an Oxidative Stress Biomarker and Plasma Haemoglobin in Patients with Chronic Kidney Disease
2010
Introduction: Evidence suggests that decreased haemoglobin plasma concentration may be a predictor of adverse cardiovascular events in patients with chronic kidney disease (CKD). We hypothesized that in CKD patients, oxidative stress could influence the development of cardiovascular damage via a relationship with haemoglobin levels. Methods: We assayed plasma levels of the biomarker of oxidative stress 8-ISO-prostaglandin F2α (8-ISO-PGF2α) and of haemoglobin in 193 stage 2–5 CKD patients, investigating their relationship. Eighty healthy subjects and 80 patients with primary hypertension having normal renal function were enrolled as controls. Results: The CKD group was divided according to 8…