Actions of Xanthurenic Acid, a putative endogenous Group II metabotropic glutamate receptor agonist, on sensory transmission in the thalamus

► Xanthurenic Acid (XA) is a novel Group II mGlu receptor ligand in vitro. ► In this study we demonstrate XA to act as a Group II mGlu receptor agonist in vivo. ► We postulate that XA is the first potential endocoid for the mGlu receptors.