The excitotoxin quinolinic acid is present and unevenly distributed in the rat brain.
The presence of quinolinic acid (2,3-pyridinedicarboxylic acid, QA) in the rat brain has been demonstrated using a mass-spectrometric method. Distribution studies indicate that this molecule is more concentrated in the cortex (2.1 nmol/g wet weight) than in other brain areas. Tryptophan, a possible QA precursor, administered in large doses, increases the cortical content of QA. The contrary occurs when rats are pretreated with p-chlorophenylalanine, a drug capable of decreasing brain tryptophan concentration. The neurotoxin 5,7-dihydroxytryptamine is inactive. Our findings support the idea that QA merits special attention as a potential transmitter and as an endogenous excitotoxin in brain.
D015116:5,7-Dihydroxytryptamine / Q000494:pharmacology; D000818:Animals; D001923:Brain Chemistry; D010134:Fenclonine / Q000494:pharmacology; D008297:Male; D013058:Mass Spectrometry; D009410:Nerve Degeneration / Q000187:drug effects; D011725:Pyridines / Q000032:analysis*; D011805:Quinolinic Acids / Q000032:analysis*; D051381:Rats / Q000378:metabolism*; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000032:analysis; D014018:Tissue Distribution; D014364:Tryptophan / Q000494:pharmacology
D011725:Pyridines; D011805:Quinolinic Acids; D015116:5,7-Dihydroxytryptamine; D012701:Serotonin; D014364:Tryptophan; D010134:Fenclonine