Search results for " oxide"

Poly-ADP ribose polymerase, xanthine oxidase and nitric oxide synthase expression in kidney tissue of experimental diabetes

2014

Background The spatial distribution of inflammatory and DNA reparation markers in the kidney tissue in diabetes is poorly understood. Aim The present study investigated the role of endothelial and inducible nitric oxide synthase (eNOS and iNOS), Poly ADP ribose polymerase (PARP) xanthine oxidase (XO) in the pathogenesis of streptozotocin-induced diabetic changes in the kidney tissue. Methods Diabetes mellitus was induced in rats by a single injection of streptozotocin (STZ) at a dose of 50 mg/kg. The XO, PARP, eNOS and iNOS protein expression in the kidney was studied by immunohistochemistry. Results Obtained results showed that STZ administration incresed the numbers of PARP and XO-positiv…

Evaluation of oxidative stress in hypertensive patients with transplanted kidney

2005

LEUKOTRIENE RECEPTORS ON HUMAN PULMONARY VASCULAR ENDOTHELIUM

1995

1. Cysteinyl-leukotrienes cause contractions and/or relaxations of human isolated pulmonary vascular preparations. Although, the localization and nature of the receptors through which these effects are mediated have not been fully characterized, some effects are indirect and not mediated via the well-described LT1 receptor. 2. In human pulmonary veins (HPV) with an intact endothelium, leukotriene D4 (LTD4) induced contraction above basal tone. This response was observed at lower concentrations of LTD4 in the presence of nitric oxide synthase inhibitor N omega-nitro-L-arginine (L-NOARG). Contractions (in the absence and presence of L-NOARG) were partially blocked by the LT1 antagonists (MK 5…

The phototransduction cascade in the isolated chick pineal gland revisited.

2003

It is well established that the isolated chick pineal gland is directly light sensitive and that melatonin synthesis of the gland can be inhibited by exposing the gland to light during scotophase. Since not all the steps of the phototransduction cascade have been clarified to the same extent as in the retina, we have treated isolated chick pineal glands with 90 min of light during scotophase and with drugs that affect key-components of vertebrate phototransduction, i.e., cyclic guanosine monophosphate (cGMP) phosphodiesterase 6 (PDE6), cGMP levels and cGMP-gated calcium channels. The endpoint measured was the activity of the rate-limiting enzyme of melatonin synthesis, arylalkylamine N-acet…

Islet beta-cell apoptosis triggered in vivo by interleukin-1beta is not related to the inducible nitric oxide synthase pathway: evidence for mitochon…

2003

IL-1beta is recognized as an effector cytokine contributing to islet beta-cell destruction during diabetes. We have previously shown in vitro that IL-1beta induces nitric oxide (NO) and beta-cell damage. Here, we show that IL-1beta administration in vivo to Wistar rats transiently increases manganese superoxide dismutase activity, whereas inducible NO synthase is not detected, and the levels of nitrate+nitrate do not change. Moreover, a significant decrease of mitochondrial aconitase, leading to a rise of hydroperoxides, and islet beta-cell apoptosis, involving caspase-3 and -8, is observed. Analysis of adhesion molecules in beta-cells showed that intercellular adhesion molecule-1 is highly…

Intraperitoneal injection of tetracyclines protects mice from lethal endotoxemia downregulating inducible nitric oxide synthase in various organs and…

1997

We have tested whether tetracyclines (TETs) are able to protect mice from lipopolysaccharide (LPS)-induced shock, a cytokine-mediated inflammatory reaction. Mice, injected with a single dose of tetracycline base (TETb; 1.5, 10 and 20 mg/kg of body weight) or doxycycline (DOXY; 1.5 mg/kg), were significantly protected from a lethal intraperitoneal injection of LPS (500 micrograms per mouse). TETs acted in early events triggered in response to LSP; in fact, they were no longer significantly protective if injected more than 1 h after the injection of endotoxin. LPS-treated mice protected by TETs showed a significant inhibition of tumor necrosis factor alpha (TNF-alpha), interleukin-1 alpha (IL…

Weaning induces NOS-2 expression through NF-κB modulation in the lactating mammary gland: importance of GSH

2005

Zaragozá, R; Miralles, VJ; Rus, AD; García, C; Carmena, R; García-Trevijano, ER; Barber, T; Pallardó, FV; Torres, L; Viña, JR. At the end of lactation the mammary gland undergoes involution, a process characterized by apoptosis of secretory cells and tissue remodelling. To gain insight into this process, we analysed the gene expression profile by oligonucleotide microarrays during lactation and after forced weaning. Up-regulation of inflammatory mediators and acute-phase response genes during weaning was found. Expression of IκBα (inhibitory κBα), a protein known to modulate NF-κB (nuclear factor-κB) nuclear translocation, was significantly up-regulated. On the other hand, there was a time-…

TREATMENT WITH SILDENAFIL PREVENTS IMPAIRMENT OF LEARNING IN RATS BORN TO PRE-ECLAMPTIC MOTHERS

2010

Pre-eclampsia is an important hypertensive pregnancy disorder and a main cause of maternal and fetal morbidity and mortality Children born from mothers with preeclampsia may present cognitive deficits The mechanisms leading to this cognitive impairment remain unclear and no treatments to improve it have been tested Pre-eclampsia is associated with impaired regulation of the nitric oxide 3 5 guanosine monophosphate cyclic (cGMP) pathway, which modulates some cognitive functions We hypothesized that alterations in the NO-cGMP pathway would be involved in the mechanisms leading to cognitive impairment in rats born to pre-eclamptic mothers and that treatment with sildenafil an inhibitor of the …

Endotheliale Dysfunktion: Pathophysiologie, Diagnostik und prognostische Bedeutung

2008

The endothelium plays a crucial role in the regulation of vascular tone. Recent studies have indicated that endothelial dysfunction develops in the presence of cardiovascular risk factors such as hypertension, diabetes mellitus, hypercholesterolemia and in chronic smokers, as well as in patients with a family history of cardiovascular disease. It has now been established that endothelial dysfunction represents the first indicator of vascular damage. Endothelial function can be assessed in coronary and peripheral conductance and resistance vessels by means of invasive and noninvasive (ultrasound-guided) methods such as intracoronary infusion of acetylcholine, the endothelium-dependent vasodi…

Nitric Oxide Synthesis in Vascular Physiology and Pathophysiology

2015

Nitric oxide (NO) is produced by three NO synthase (NOS) isoforms: neuronal NOS (nNOS), inducible NOS (iNOS), and endothelial NOS (eNOS). Under physiological conditions, vascular NO is produced by eNOS and nNOS, with both playing atheroprotective roles. Under pathological conditions, iNOS can be induced and eNOS may become uncoupled. iNOS produces a large amount of NO, induces vascular dysfunction, and promotes atherogenesis. Uncoupled eNOS generates superoxide instead of NO and contributes significantly to endothelial dysfunction and atherogenesis. Major mechanisms of eNOS uncoupling include depletion of tetrahydrobiopterin, an essential co-factor for the eNOS enzyme, and deficiency of L-a…