The uptake and metabolism of nicotinic acid, nicotinamide, and quinolinic acid at physiological concentrations by perfused rat liver have been studied. At a level of 400 mpmoles per liver, nicotinic acid was a more effective precursor of NAD than was nicotinamide. Labeled NAD in the liver reached maximum levels 10 min after nicotinic acid was added to the perfusate. When nicotinamide was the su...

1. The effect of quinolinic acid, N-methyl-D,L-aspartate (NMDLA) and kainate on the release of endogenous and exogenous amino acids from the rat cerebral cortex in vitro and in vivo was studied. 2. Neither quinolinic acid nor NMDLA had any effect on the basal or potassium-evoked release of [3H]-D-aspartate from slices of rat cerebral cortex either in the presence or absence of magnesium. Kainic...

The pyridine moieties of the pyridine nucleotides, nicotinic acid mononucleotide, nicotinic acid adenine dinucleotide, and nicotinamide adenine dinucleotide, were shown to be incorporated into ricinine by Ricinus communis L. with an efficiency comparable to that of quinolinic acid, nicotinic acid, and nicotinamide, which had been established previously as being efficient precursors of this alka...

The pyridine moieties of the pyridine nucleotides, nicotinic acid mononucleotide, nicotinic acid adenine dinucleotide, and nicotinamide adenine dinucleotide, were shown to be incorporated into ricinine by Ricinus communis L. with an efficiency comparable to that of quinolinic acid, nicotinic acid, and nicotinamide, which had been established previously as being efficient precursors of this alka...

A crude enzyme preparation from a nadA mutant of Escherichia coli was used to catalyze the conversion of [14C]aspartic acid into a precursor of quinolinic acid, a key intermediate in the biosynthesis of nicotinamide adenine dinucleotide.

3-Hydroxyanthranilic acid has been shown to serve as a natural precursor of niacin in Neurospora. 12 Little. information, however, has been obtained concerning the mechanism whereby the aromatic ring of 3hydroxyanthranilic acid is converted to the pyridine ring of niacin. The present paper will deal with this latter problem. Singal, et al.,I have reported that the administration of tryptophan t...

In just under 20 years the kynurenine family of compounds has developed from a group of obscure metabolites of the essential amino acid tryptophan into a source of intensive research, with postulated roles for quinolinic acid in neurodegenerative disorders, most especially the AIDS-dementia complex and Huntington’s disease. One of the kynurenines, kynurenic acid, has become a standard tool for ...