Ascorbate is readily oxidized in aqueous solution by ascorbate oxidase. Ascorbate radicals are formed, which disproportionate to ascorbate and dehydroascorbic acid. Addition of erythrocytes with increasing intracellular ascorbate concentrations decreased the oxidation of ascorbate in a concentration-dependent manner. Concurrently, it was found, utilizing electron spin resonance spectroscopy, th...

the effects of chronic administration of lithium, on acute toxicity of carbamazepine (cbz) in mate albino mice was studied and the ld50 values were determined from dose-probit curves. the results showed that in lithium pretreated animals (animals consumed drinking water contraining 600 mg/l lithium carbonate for 10 days) the ld50 value (the doese corresponding to probit 5) of cbz decreased sign...

the effects of chronic administration of lithium, on acute toxicity of chlorpromazine (cpz) in male albino mice was studied and the ldso values were determined from dose-probit curves. tfie results showed that in lithium pretrealed animals (anmials consumed drinking water containing 600mg/l lithium chloride for 10 days) the ld50 value (the dose corresponding to probit 5) of cpz increased signif...

Ascorbate (vitamin C) recycling occurs when extracellular ascorbate is oxidized, transported as dehydroascorbic acid, and reduced intracellularly to ascorbate. We investigated microorganism induction of ascorbate recycling in human neutrophils and in microorganisms themselves. Ascorbate recycling was determined by measuring intracellular ascorbate accumulation. Ascorbate recycling in neutrophil...

trehalose is an important disaccharide signal metabolite in plants which is involved in various aspects of plant function such as response to stress, photosynthesis and carbon allocation and partitioning. a mutant of arabidopsis lacking trehalose-6-phosphate synthase activity (tps1) accumulates ascorbate. exogenous ascorbate application ameliorates trehalose induced growth inhibition of wild ty...

Ascorbate has previously been shown to enhance both alpha(1)- and beta(2)-adrenergic activity. This activity is mediated by ascorbate binding to the extracellular domain of the adrenergic receptor, which also decreases the oxidation rate of ascorbate. H1 histamine receptors have extracellular agonist or ascorbate binding sites with strong similarities to alpha(1-) and beta(2)-adrenergic recepto...

Despite its transport by glucose transporters (GLUTs) in vitro, it is unknown whether dehydroascorbic acid (oxidized vitamin C, DHA) has any in vivo function. To investigate, we created a chemical transport knockout model using the vitamin C analog 6-bromo-ascorbate. This analog is transported on sodium-dependent vitamin C transporters but its oxidized form, 6-bromo-dehydroascorbic acid, is not...

The chemiluminescence of gallic acid by hydrogen peroxide had completely inhibited by the presence of ascorbate. After ascorbate had disappeared by oxidation, chemiluminescence returned. The concentration of gallic acid was virtually unchanged by presence of ascorbate, but started to decrease after the disappearance of ascorbate. This might be attributable to the rapid reduction of quinone, whi...

Ascorbate levels and redox state, as well as the activities of the ascorbate related enzymes, have been analysed both in the apoplastic and symplastic spaces of etiolated pea (Pisum sativum L.) shoots during cellular differentiation. The ascorbate pool and the ascorbate oxidizing enzymes, namely ascorbate oxidase and ascorbate peroxidase, were present in both pea apoplast and symplast, whereas ...