Exposure to Kynurenic Acid During Adolescence Produces Memory Deficits in Adulthood

The glia-derived molecule kynurenic acid (KYNA) is an antagonist of a7 nicotinic acetylcholine receptors and the glycineB binding site on n-methyl-d-aspartateglutamate receptors,bothofwhichhavecritical roles inneuralplasticity as well as learning and memory. KYNA levels are increased in the brains and cerebral spinal fluid of persons with schizo-phrenia, leading to thenotion that changes inKYNAconcen-trationmight contribute to cognitive dysfunction associated with this disorder. Indeed, recent studies indicate that in-creasingendogenousKYNAconcentrationbyadministering l-kynurenine (L-KYN, theprecursorofKYNA) impairs spa-tial as well as contextual learning andmemory in adult rats. In the present study, ratswere treatedwithL-KYN(100mg/ kg) throughout adolescence to increase endogenous KYNA concentration during this critical time in brain development