It is well known that nitrate is an important nutrient that supports plant growth and development. The application of nitrate also causes extensive changes in the expression of genes coding for proteins involved in nitrogen (N) metabolism. Indeed, genomic analyses have provided a comprehensive dataset of more than a thousand nitrate-responsive genes in Arabidopsis (Arabidopsis thaliana). Much l...

In high enough concentrations, such as produced by inducible nitric oxide synthase (iNOS), reactive nitrogen species (RNS) can kill Mycobacterium tuberculosis (Mtb). Lesional macrophages in macaques and humans with tuberculosis express iNOS, and mice need iNOS to avoid succumbing rapidly to tuberculosis. However, Mtb's own ability to produce RNS is rarely considered, perhaps because nitrate red...

Salivary nitrate from dietary or endogenous sources is reduced to nitrite by oral bacteria. In the acidic stomach, nitrite is further reduced to bioactive nitrogen oxides, including nitric oxide (NO). In this study, we investigated the gastroprotective role of nitrate intake and of luminally applied nitrite against provocation with diclofenac and taurocholate. Mucosal permeability ((51)Cr-EDTA ...

Plasma nitrite and nitrate determinations are increasingly being used in clinical chemistry as markers for the activity of nitric oxide synthase and the production of nitric oxide radicals. However, a systematic evaluation of the determination of nitrite and nitrate in plasma has not been performed. In this study the recovery and stability of nitrite and nitrate in whole blood and in plasma, th...

Plasma levels of nitrite ions have been used as an index of nitric oxide synthase (NOS) activity in vivo. Recent data suggest that nitrite is a potential intravascular repository for nitric oxide (NO), bioactivated by a nitrite reductase activity of deoxyhemoglobin. The precise levels and compartmentalization of nitrite within blood and erythrocytes have not been determined. Nitrite levels in w...

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 ...

Induction and repression of denitrification activity were studied in a continuous culture of Paracoccus denitrificans during changes from aerobic to anaerobic growth conditions and vice versa. The denitrification activity of the cells was monitored by measuring the formation of denitrification products (nitrite, nitric oxide, nitrous oxide, and dinitrogen), individual mRNA levels for the nitrat...

The pathway of anaerobic reduction of nitrite to nitrogen gas (N2) by cell suspensions of the denitrifier, Pseudomonas aeruginosa, was studied using the techniques of gas chromatography and mass spectrometry. While release of nitrous oxide (N2O) is not normally detected during the reduction of nitrite to N2 by this organism, 15N from [15N]nitrite nevertheless can be trapped quantitatively as 15...

Nitrite was once thought to be inert in human physiology. However, research over the past few decades has established a link between nitrite and the production of nitric oxide (NO) that is potentiated under hypoxic and acidic conditions. Under this new role nitrite acts as a storage pool for bioavailable NO. The NO so produced is likely to play important roles in decreasing platelet activation,...

The aim of this investigation was to determine nitric oxide metabolite levels in saliva samples from hepatitis C virus-positive patients in an attempt to test the hypothesis if increased levels of nitric oxide metabolites correlates with the presence of HCVRNA in saliva. Saliva of 39 HCV-positive patients and 13 HCV-negative patients, without clinical or laboratorial evidence of liver disease w...