Changes in kynurenic, anthranilic and quinolinic acid concentration in rat brain tissue during developement

Kynurenic, anthranilic, and quinolinic acid, brain tissue concentrations and indoleamine 2,3-dioxygenase [EC 1 13.11.17] activity were determined in rat brain, during pre- and postnatal development. Quinolinic acid brain tissue concentration was significantly increased at birth ascompared with the prenatal level, then it declined rapidly in the postnatal period. By the contrary,kynurenic and anthranilic acids brain tissue concentrations in rat brain were significantly lowerat birth as compared with those found prenatally; then kynurenic acid concentration decreasedin the first postnatal week and increased thereafter, while anthranilic acid concentration increased in the first postnatal week and decreased thereafter. Indoleamine 2,3-dioxygenase [EC 113.11.17] activity were found unchanged in pre and post natal rat brain. The described oppositechanges in quinolinic and kynurenic acids concentrations, occurring in pre- and postnatal period,despite the lack of knowledge on the precise role played by these compounds on the differentneurotransmitter systems in the brain, could be involved in brain ontogenetic development.