Quinolinic acid inhibits DOI-induced head shakes in mice

Abstract

Quinolinic acid, a metabolite of tryptophan in the kynurenine pathway, inhibited the 5-HT2A/2C direct agonist (+)-1-(2,5-dimethoxy-4-iodophenyl)-2-amino propane hydrochloride (DOI) induced head shakes in mice in a dose-dependent manner. This e¡ect was observed 10 min after intracerebroventricular (i.c.v.) administration of 0.06251 mg/mouse. 3-Hydroxyanthranilic acid, which is the immediate stable precursor of quinolinic acid in the kynurenine pathway, showed a similar e¡ect 60120 min after subcutaneous (s.c.) administration, without showing any e¡ect 10 min after i.c.v. administration or 2040 min after s.c. administration. These observations suggest that quinolinic acid can alter central e¡ects mediated via 5-HT_2A receptors.