Ontogeny of ionotropic glutamate receptor expression in human fetal brain

Glutamate receptors have multiple roles in the central nervous system. Rece nt evidence suggests that the iontropic glutamate receptors are critical du ring brain development, particularly fur corticogenesis, neuronal migration . and synaptogenesis. In this study, we examined subunit mRNA expression an d binding sites of the NMDA, AMPA, and kainate receptors from gestational w eeks 8-20 in human fetal brain. Expression of glutamate receptors was high during several periods in these brains. Different levels of expression of e ach NMDA, AMPA, and kainate receptor subunit transcripts were present durin g development, with a greater abundance of NR1, NR2B, NR2D, GluR7, and KA1 mRNA at most gestational ages. Binding sites for NMDA, AMPA, and kainate re ceptors were all detected, but each had a unique pattern of expression. The se results demonstrate that glutamate receptors are expressed early in huma n brain development, and undergo complex changes over time consistent with their role in normal development. (C) 2001 Elsevier Science B.V. All rights reserved.