Notes: Quinolinic acid is an active metabolite of tryptophan (Item Nos. 29600 / 31210) and an NMDA receptor agonist.{23856,51251} It is formed from tryptophan via the kynurenine pathway.{23856} Quinolinic acid (100 µM) induces lipid peroxidation in rat brain synaptosomes, an effect that can be reversed by the NMDA receptor antagonist 2-amino-5-phosphonovaleric acid.{24465} It decreases the viability of primary rat neurons when used at a concentration of 25 µM.{38621} Intracerebroventricular administration of quinolinic acid (1 µg/animal) induces convulsions in mice.{51252} Increased plasma levels of quinolinic acid negatively correlate with Brief Neurocognitive Assessment (BNA) scores in patients with schizophrenia.{51253}