Quinolinic acid evokes [3H]acetylcholine release in striatal slices: mediation by NMDA-type excitatory amino acid receptors.

Quinolinic acid evoked the release of [3H]acetylcholine from striatal slices with an EC50 of approximately 2 mM and an efficacy similar to that of N-methyl-D,L-aspartic acid. (+/-)-2-Amino-5-phosphonopentanoic acid and (-)-2-amino-7-phosphonoheptanoic acid antagonized quinolinic acid-evoked release, while glutamate diethylester and 2-amino-4-phosphonobutyric acid were ineffective as antagonists. Release of [3H]acetylcholine evoked by quinolinic acid was strongly attenuated by the presence of magnesium (1.2 mM) in the medium. The results are consistent with the interaction of quinolinic acid with NMDA-type excitatory amino acid receptors on the striatal cholinergic interneurons.