Upregulation of xanthine oxidoreductase (XOR) increases vascular reactive oxygen species (ROS) levels and contributes to nitroso-redox imbalance. However, XOR can generate nitric oxide (NO) from nitrite, and increased superoxide could inactivate NO formed from nitrite. This study tested the hypothesis that XOR contributes to the cardiovascular effects of nitrite in renovascular hypertension, an...

RECENT EXPERIMENTAL EVIDENCE suggests that the anion nitrite represents an important storage form of nitric oxide (NO) that subsequently regulates a number of very important physiological activities (2–5, 10). This is a radical concept because nitrite was largely considered to be a biologically inert breakdown product of NO that served no physiological purpose. In fact, circulating nitrite leve...

A long-term sodium nitrite infusion is intended for the treatment of vascular disorders. Phase I data demonstrated a significant nonlinear dose-exposure-toxicity relationship within the therapeutic dosage range. This study aims to develop a quantitative systems pharmacology model characterizing nitric oxide (NO) metabolome and methemoglobin after sodium nitrite infusion. Nitrite, nitrate, and m...

Nitrate serves as a potent signal to control gene expression in plants and algae, but little is known about the signaling role of nitrite, the direct product of nitrate reduction. Analysis of several nitrate-induced genes showed that nitrite increases mRNA levels as rapidly as nitrate in nitrogen-starved Arabidopsis (Arabidopsis thaliana) roots. Both nitrite and nitrate induction are apparent a...

Sodium nitrite, a common food additive, exists widely not only in the environment but also in our body. Excessive nitrite causes toxicological effects on human health; however, whether it affects vertebrate heart valve development remains unknown. In vertebrates, developmental defects of cardiac valves usually lead to congenital heart disease. To understand the toxic effects of nitrite on valvu...

A kinetic method developed for the determination of ultra-trace amounts of nitrite based on its catalytic effect on the reaction between potassium bromate and Nile blue A in strongly acidic media is reported. The reaction was monitored spectrophotometrically by measuring the decrease in absorbance of Nile blue A at 645 nm by the fixed-time method. The decrease in absorbance during the first...

addition of n-butyl nitrite to isolated rat hepatocytes caused an immediate glutathione depletion followed by an inhibition of mitochondrial respiration, inhi- bition of glycolysis and atp depletion. at cytotoxic butyl nitrite concentrations, lipid  peroxidation  occurred  before  the  plasma  membrane  was  disrupted. cytochrome p-450 inhibitors inhibited peroxynitrite formation and prevented ...

The effect of sodium nitrite, amyl nitrite and nitroglycerin (glyceryl trinitrate) on the hemoglobin of adult erythrocytes was examined in vitro. Both amyl nitrite and nitroglycerin reacted immediately with oxyhemoglobin to effect oxidation into methemoglobin while sodium nitrite required an inductionary period (lag phase) prior to the reaction. Kinetic studies of the biomolecular rate law for ...