The PI hypothesizes that maternal inflammation alters TRP metabolism in the placenta by perturbing the 5-hydroxytryptophan (5- HT) and kynurenine pathways, which has significant consequences for neurodevelopment. The PI's specific aims are: 1) To determine whether maternal inflammation alters placental synthesis and fetal exposure of 5-HT and kynurenine-pathway compounds; 2) To characterize the inflammation-mediated alternations of TRP metabolism effects on fetal brain neurochemistry and postnatal brain structure; 3) To determine if genetic or pharmacological manipulations of placental TRP metabolic pathways in vivo can reduce inflammation effect on offspring brain development.