Search results for "Oxide"
showing 10 items of 6424 documents
Nitric oxide in the pathogenesis of vascular disease
2000
Nitric oxide (NO) is synthesized by at least three distinct isoforms of NO synthase (NOS). Their substrate and cofactor requirements are very similar. All three isoforms have some implications, physiological or pathophysiological, in the cardiovascular system. The endothelial NOS III is physiologically important for vascular homeostasis, keeping the vasculature dilated, protecting the intima from platelet aggregates and leukocyte adhesion, and preventing smooth muscle proliferation. Central and peripheral neuronal NOS I may also contribute to blood pressure regulation. Vascular disease associated with hypercholesterolaemia, diabetes, and hypertension is characterized by endothelial dysfunct…
eNOS Uncoupling in Cardiovascular Diseases - the Role of Oxidative Stress and Inflammation
2013
Many cardiovascular diseases and drug-induced complications are associated with - or even based on - an imbalance between the formation of reactive oxygen and nitrogen species (RONS) and antioxidant enzymes catalyzing the break-down of these harmful oxidants. According to the “kindling radical” hypothesis, the formation of RONS may trigger in certain conditions the activation of additional sources of RONS. According to recent reports, vascular dysfunction in general and cardiovascular complications such as hypertension, atherosclerosis and coronary artery diseases may be connected to inflammatory processes. The present review is focusing on the uncoupling of endothelial nitric oxide synthas…
Dexamethasone suppresses eNOS and CAT-1 and induces oxidative stress in mouse resistance arterioles
2004
Long-term treatment with glucocorticoids is associated with mild to moderate hypertension. We reported previously that downregulation of endothelial NO synthase (eNOS) expression and activity is likely to contribute to this increase in blood pressure. In the present study, we tested the effects of dexamethasone on the vasodilation of microvascular arterioles using implanted dorsal skin-fold chambers in anesthetized C57BL/6J mice. Experiments were performed on control mice or on mice treated with dexamethasone (0.1–3 mg/kg of body wt). Endothelium-dependent vasodilation in response to ACh (0.1–10 μM) was reduced by dexamethasone in a dose-dependent fashion. Comparable inhibition was seen in …
PPARγ as an indicator of vascular function in an experimental model of metabolic syndrome in rabbits
2021
Abstract Background and aims Underlying mechanisms associated with vascular dysfunction in metabolic syndrome (MetS) remain unclear and can even vary from one vascular bed to another. Methods In this study, MetS was induced by a high-fat, high-sucrose diet, and after 28 weeks, aorta and renal arteries were removed and used for isometric recording of tension in organ baths, protein expression by Western blot, and histological analysis to assess the presence of atherosclerosis. Results MetS induced a mild hypertension, pre-diabetes, central obesity and dyslipidaemia. Our results indicated that MetS did not change the contractile response in either the aorta or renal artery. Conversely, vasodi…
Focal elevation of liver microsomal epoxide hydrolase in early preneoplastic stages and its behaviour in the further course of hepatocarcinogenesis.
1981
Abstract Treatment of rats with N-nitrosomorpholine (NNM) for 7 weeks led to a focal increase in liver microsomal epoxide hydrolase (EH) as early as 2 weeks after withdrawal of the carcinogen. This treatment also leads to hyperplastic nodules and liver tumors, but much later. At the same early time point, ATPase activity was decreased in the same islands. Most of these areas already had increased γ-glutamyltranspeptidase activity. The increase in EH at this early time point was more distinct than the decrease in ATPase which has thus far been considered a suitable marker of the earliest stages in hepatocarcinogenesis. The focal increase in EH was also observed in all benign hepatomas, but n…
Analgesic and physiological effects in conscious sedation with different nitrous oxide concentrations
2015
Objectives: to study the physiological changes, as well as the psychosedative and analgesic effects of nitrous oxide, in experimental conditions. Study Design: 101 dental students volunteers participated in a single nitrous oxide sedation session without dental treatment. Signs and symptoms were registered during and after the procedure. Pulse rate and hemoglobin oxygen saturation were monitored at: 100 per cent O 2 , 30 per cent N 2 O, 50 per cent N 2 O and 5 minutes after 100 per cent O 2 . A Likert scale was used to evaluate pain perception. The analgesic effects of nitrous oxide were evaluated at: 30 per cent N 2 O, 50 per cent N 2 O, and five minutes postoperatively. Results: Pulse rat…
Theoretical Basis Versus Clinical Practice of Oxygen Parameters of Blood
1996
Under optimal conditions all oxygen parameters of human blood are defined at a theoretical basis, accepted and understood by the clinicians, measured correctly by instruments of different manufacturers and, therefore, leading to clear diagnoses for the patients.
LSC Abstract – Oxidative stress in nasal epithelial cells from patients with primary ciliary dyskinesia
2016
Background: Primary ciliary dyskinesia (PCD) is a rare autosomal recessive inheritance disorder characterized by dysfunction of respiratory cilia and impaired mucociliary clearance, leading to respiratory problems appearing in childhood, decreased fertility and situs inversus in 50% of the cases. The deficient ciliary movement causes stasis of secretions in the airways leading to recurrent airway infection and chronic inflammation. Rationale and aims: Chronic inflammation has been associated to oxidative stress (OS). Moreover, evidence of increased OS in the airways of stable children with PCD has been shown (Zihlif, N. et al . Pediatr Pulmonol 2006; 41:509-14.). Therefore, we hypothesize t…
Pancreatic ascites haemoglobin up-regulates the HIF/VEGF pathway in the lung in severe acute pancreatitis
2015
Extracellular haemoglobin (EHb) is considered a toxic molecule due to its cytotoxicity and peroxidase activity. EHb may release free hemin that increases vascular permeability, leukocyte recruitment, and adhesion molecule expression. Pancreatitis-associated ascitic fluid is reddish and may contain cell-free hemoglobin. Our aim was to determine the role of EHb in the local and systemic inflammatory response during severe acute pancreatitis in rats. To this end, taurocholate-induced necrotizing pancreatitis in rats was used. EHb levels were quantified in ascites and plasma and the hemolytic action of ascitic fluid was tested. Furthermore, we assessed if peritoneal lavage prevented the increas…
Oxidative stress induces myeloperoxidase expression in endocardial endothelial cells from patients with chronic heart failure.
2009
Increased oxidative stress has been implicated in the pathogenesis of a number of cardiovascular diseases. Recent findings suggest that myeloperoxidase (MPO) may play a key role in the initiation and maintenance of chronic heart failure (CHF) by contributing to the depletion of the intracellular reservoir of nitric oxide (NO). NO consumption through MPO activity may lead to protein chlorination or nitration, leading to tissue damage. Primary cultures of human endocardial endothelial cells (EEC) obtained at heart transplantation of patients with CHF and human umbilical vein endothelial cells (HUVEC) were subjected to oxidative stress by incubation with hydrogen peroxide at non lethal (60 mic…