The ontogeny of glutamate receptors and D-aspartate binding sites in the ovine CNS

The ontogeny of ligand binding to N-methyl-D-aspartate (NMDA), alpha-amino- 3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and kainate (KA) recept ors and to the high affinity, sodium-dependent D-aspartate binding site in prenatal and postnatal ovine brains was studied using quantitative in vitro autoradiography. In general, the binding density for each of the excitator y amino acid receptors peaked during late prenatal and early postnatal deve lopment. In contrast, binding density for D-aspartate remained low during l ate prenatal and early postnatal development and peaked in the adult. These data suggest that an excess number of excitatory amino acid receptors and/ or a relative deficiency of transporters may make the immature brain more v ulnerable to the pathologic effects of glutamate and other related excitato ry amino acids. (C) 1999 Elsevier Science B.V. All rights reserved.