Oxidative stress in distant organs and the effects of allopurinol during experimental acute pancreatitis.

Background: The present study was aimed at an assessment of the role of oxygen-derived free radicals in the development of local and systemic manifestations of L-arginine (Arg)-induced acute pancreatitis and at an evaluation of the protective effect of the xanthine oxidase inhibitor allopurinol.

Methods: Acute pancreatitis was induced in male Wistar rats by injecting 2 x 250 mg/100 g body weight of Arg intraperitoneally at an interval of 1 h, as a 20% solution in 0.15 M NaCl.

The pathogenesis of L-arginine-induced acute necrotizing pancreatitis: inflammatory mediators and endogenous cholecystokinin.

This study was aimed at an assessment of the role of oxygen-derived free radicals, cytokines and endogenous cholecystokinin (CCK) in the pathogenesis of L-arginine (Arg)-induced acute pancreatitis in rat. We measured the levels of malonyl dialdehyde (MDA), glutathione peroxidase (GPx), catalase and superoxide dismutase (Mn- and Cu, Zn-SOD) in pancreatic tissue, the serum levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and CCK, and evaluated the protective effect of the xanthine oxidase inhibitor allopurinol and a novel CCK receptor antagonist KSG-504. Acute pancreatitis was induced in male Wistar rats by injecting 2x 250 mg/100 g body weight of Arg intraperitoneally in an 1-h interval, as a 20% solution in 0.

Changes in cardiac electrophysiology, morphology, tissue biochemistry and vascular reactions in glutathione depleted animals.

The effects of acute and chronic glutathione depletion (single i.p. injection of 3 mmol/kg L-buthionine-S,R-sulphoximine and 2 mmol/kg for 4 days) on heart action potential (AP) characteristics, electronmicroscopy, cytochemistry and biochemistry and vascular contractility and nitric oxide-mediated relaxation were studied in rats and guinea pigs.

Involvement of oxygen-derived free radicals in L-arginine-induced acute pancreatitis.

This study was aimed at an assessment of the role of oxygen-derived free radicals in the pathogenesis of L-arginine (Arg)-induced acute pancreatitis in rat, by measuring the levels of malonyl dialdehyde (MDA), glutathione peroxidase (GPx), catalase, and superoxide dismutase (Mn- and Cu,Zn-SOD) in the pancreatic tissue, and evaluating the protective effect of the xanthine oxidase inhibitor allopurinol. Acute pancreatitis was induced in male Wistar rats by injecting 2 x 250 mg/100 g body weight of Arg intraperitoneally in a 1-hr interval, as a 20% solution in 0.15 M NaCl.

Organophosphate effects on antioxidant system of carp (Cyprinus carpio) and catfish (Ictalurus nebulosus).

The effect of the organophosphate insecticide Dichlorvos on antioxidant enzymes and other oxidative and redox parameters of carp (Cyprinus carpio L.) and catfish (Ictalurus nebulosus) were studied. Changes in superoxide dismutase, catalase, glutathione peroxidase, and in the case of carp acetylcholinesterase activities were studied in tissue homogenates.

Oxidative stress changes in L-arginine-induced pancreatitis in rats.

The important role of oxygen radicals in acute experimental pancreatitis was demonstrated by study of the changes in the antioxidant system in the blood, liver, kidney, and pancreas of rats after the administration of a large quantity of L-arginine (L-Arg). The changes in lipid peroxidation and in reduced and oxidized glutathione were followed, as well as the activities of peroxide-decomposing enzymes (glutathione peroxidase and catalase) and H2O2-producing superoxide dismutases. The results demonstrated that "oxidative stress" develops and acute pancreatitis appears rapidly after L-Arg treatment.

The activation by magnesium treatment of anti-oxidants eliminating the oxygen free radicals in Drosophila melanogaster in vivo.

Drosophila melanogaster adults of the Oregon R and Canton S wild-type stocks were fed for 24 h with 0.10 M, 0.25 M and 0.

Further prove on oxidative stress in alloxan diabetic rat tissues.

After intravenous administration of alloxan monohydrate (AL) diabetes developed in rats. Forty-eight hours after the injection the animals were sacrificed, their blood was collected in heparin containing tubes and the tissues were dissected and frozen (-70 degrees C) until their homogenization for pro- and antioxidant testing. Our results can be summarised as follows: (i) In the blood hemolysate the lipid peroxidation slightly elevated and the activity of antioxidant enzymes and reduced glutathione decreased.

Lipid peroxidation and antioxidant system changes in acute L-arginine pancreatitis in rats.

The important role of oxygen radicals in acute experimental pancreatitis was demonstrated by study of the changes in the antioxidant system in the blood, liver, kidney and pancreas of rats after the administration of a large quantity of L-arginine (L-Arg). The changes in lipid peroxidation and in reduced and oxidized glutathione were followed as well as the activities of peroxide-decomposing enzymes (glutathione peroxidase and catalase) and H2O2-producing superoxide dismutases. The results demonstrated that acute pancreatitis and "oxidative stress" develop rapidly after L-Arg treatment.

Pro-, antioxidant and filtration changes in the blood of type 1 diabetic patients.

In our present work we attempt to clarify the pro-, antioxidant status (redox status) of blood and the red blood cell (RBC) filtration changes in type 1 (insulin dependent diabetes mellitus = IDDM) diabetic patients, broadening our biochemical knowledge about the mechanism of disease. Further on we try to apply our observations in therapy. Our studies on enzymes and the pro- and antioxidant status in type 1 diabetes are closely related to earlier works.

Oxidative stress in experimental diabetes induced by streptozotocin.

It is known that streptozotocin (STZ) penetrating into the organism generates nitrogen monoxide (NO). Therefore, it is justified to presume, that in beta-cell destruction thereby induced, peroxinitrit resulting from NO and superoxide (O2-) reaction has an important role. It has also been studied how pro- and antioxidant systems change in STZ induced experimental diabetes in rat organs.

Effects of diethyl-dithiocarbamate on antioxidant system in carp tissue.

The influence the pro- and antioxidant values the diethyl-dithiocarbamate (DDTC) in different concentrations in carp tissues was studied. From antioxidant enzyme superoxide dismutase, catalase and glutathion peroxidase activity changes were studied in tissue homogenates. Beside enzyme activities tissue lipid peroxidation (LP), reduced glutathione (GSH) and hydroxyl radical loading of the tissues were measured.

Oxidative stress and antioxidant defense mechanism in glomerular diseases.

The changes in red blood cell (RBC) lipid peroxidation [measured via the malonyl dialdehyde (MDA) concentration], reduced (GSH), and oxidized glutathione (GSSG) levels, hemoglobin (Hb) oxidation and antioxidant enzyme [catalase (Cat), glutathione peroxidase, and superoxide dismutase (SOD)] activities were studied in 45 pediatric patients with various glomerular diseases [minimal change nephrotic syndrome (MCNS) in relapse or in remission, lupus nephropathy (SLE), poststreptococcal glomerulonephritis (APSGN), IgA nephropathy (IGA gn)], and in 20 adult patients with IGA gn and also in 15 pediatric and 14 adult controls. The in vitro effects of hydrogen peroxide [acetyl phenylhydrazine (APH) test] on the GSH and Hb metabolisms were likewise investigated. There was an increased oxidative stress in MCNS with relapse, IGA gn, SLE gn, and APSGN, which could be detected in the GSH and Hb oxidation and in the lipid peroxidation on the peripheral RBC-s.

Effect of glutathione depletion on electrophysiological characteristics of guinea-pig ventricles.

In this study the effect of acute and chronic glutathione depletion with L-buthionine-S,R-sulphoximine (BSO) on action potential characteristics of guinea-pig left ventricle papillary muscles were investigated. BSO caused significant decrease of maximum rate in rise of depolarization phase (Vmax) and duration of AP (APD) at 25%, 50%, 90% of repolarization in both cases of depletion and a slight but not significant decrease in the action potential amplitude, but did not modify the resting membrane potential. Pretreatment with bisaramil prevented the effect of BSO on APD in both cases of depletion.

[Hemo-rheologic and antioxidant changes in acute human pancreatitis].

In earlier studies of authors on acute and intermittent human pancreatitis it appeared that oxygen radicals may have important role in inflammations of pancreas. Therefore, detailed and systematic studies have been started in order to understand the rheological characteristics of human red blood cells (RBCs), antioxidant enzymes and other antioxidant parameters in clinically serious acute pancreatitis. Measurements of antioxidant system of blood, plasma and haemolysates have indicated prooxidant preponderance, and have apparently well reflected the "oxidative stress" conditions of the organism.

Effects of an organophosphate on the antioxidant systems of fish tissues.

The effect of a Hungarian made and applied insecticide, organophosphate (Dichlorvos) on antioxidant enzymes and other oxidative and redox parameters of two different fish species, carp (Cyprinus carpio L.) and catfish (Ictalurus nebulosus) was studied. The two fish species have different ways of life.

Platelet membrane fluidity and plasma malondialdehyde levels in Alzheimer's demented patients with and without family history of dementia.

Platelet membrane fluidity (PMF) was measured with three different fluorescent probes, 1,6-diphenyl-1,3,5-hexatriene (DPH), 1-(4-trimethylammoniumphenyl)-6-phenyl-1,3,5-hexatriene (TMA-DPH), 3-(p-phenyl-1,3,5-hexatrienyl)phenyl-propionic acid (DPH-PA), which labeled different parts of the bilayer (the hydrophobic core and the positively and negatively charged regions, respectively) in Alzheimer's disease (AD) patients with and without a family history of dementia, and in a control group. In support of earlier findings in the literature, significantly increased PMF was found by the application of DPH in both groups with AD. The use of the fluorescence probe TMA-DPH, however, revealed no differences between the groups.

Oxidative damage of red blood cells in haemolytic uraemic syndrome.

Changes in red blood cell (RBC) lipid peroxidation [measured by malonyl dialdehyde (MDA) concentration], glutathione (GSH) metabolism, antioxidant enzyme activities (catalase, superoxide dismutase, glutathione peroxidase) and haemoglobin (Hb) metabolites (metHb, carboxy Hb) were studied in six children with post-enteropathic (D+) haemolytic uraemic syndrome (HUS) and ten controls. The in vitro effect of hydrogen peroxide [acetylphenylhydrazine (APH) test] on GSH and Hb metabolism was also investigated. MDA levels were significantly higher and the antioxidant enzyme activities were lower in HUS patients than in the controls (P < 0.

The role of free radicals and antioxidative enzymes in erythrocytes and liver cells in the course of Plasmodium berghei and Plasmodium vinckei infection of mice.

Blood schisontocidal test of D0 + D3 type revealed different characteristics of the Plasmodium berghei and Plasmodium vinckei infection. Both types of the rodent plasmodia kill the untreated mice. Chloroquine treatment alone does not prevent the death of the P.

The effect of erythropoietin on the cellular defence mechanism of red blood cells in children with chronic renal failure.

The glutathione redox system, haemoglobin (Hb) oxidation, the activity of antioxidant enzymes and the lipid peroxidation product malonyl dialdehyde (MDA) were studied in red blood cells (RBCs) during administration of recombinant human erythropoietin (rhEPO) over 12 weeks in ten children maintained on haemodialysis. A rapid increase in the reticulocyte count was accompanied by a slower rise in total Hb concentration. The mean level of oxidized glutathione (GSSG) increased from 13.