RT Journal Article SR Electronic T1 Reelin, Very-Low-Density Lipoprotein Receptor, and Apolipoprotein E Receptor 2 Control Somatic NMDA Receptor Composition during Hippocampal Maturation In Vitro JF The Journal of Neuroscience JO J. Neurosci. FD Society for Neuroscience SP 6127 OP 6136 DO 10.1523/JNEUROSCI.1757-05.2005 VO 25 IS 26 A1 Mélanie Sinagra A1 Danièle Verrier A1 Daniela Frankova A1 Kimberly M. Korwek A1 Jaroslav Blahos A1 Edwin J. Weeber A1 Olivier J. Manzoni A1 Pascale Chavis YR 2005 UL http://www.jneurosci.org/content/25/26/6127.abstract AB Reelin is a secreted protein that regulates brain layer formation during embryonic development. Reelin binds several receptors, including two members of the low-density lipoprotein (LDL) receptor family, the apolipoprotein E receptor 2 (ApoER2) and the very-low-density lipoprotein receptor (VLDLR). Despite the high level of expression of Reelin and ApoER2 in the postnatal brain, their functions in the adult CNS remain elusive. Here, using electrophysiological, immunocytochemical, and biochemical approaches in cultured postnatal hippocampal neurons, we show that Reelin controls the change in subunit composition of somatic NMDA glutamate receptors (NMDARs) during maturation. We found that maturation is characterized by the gradual decrease of the participation of NR1/2B receptors to whole-cell NMDAR-mediated currents. This maturational change was mirrored by a timely correlated increase of both Reelin immunoreactivity in neuronal somata and the amount of secreted Reelin. Chronic blockade of the function of Reelin with antisense oligonucleotides or the function-blocking antibody CR-50 prevented the decrease of NR1/2B-mediated whole-cell currents. Conversely, exogenously added recombinant Reelin accelerated the maturational changes in NMDA-evoked currents. The maturation-induced change in NMDAR subunits also was blocked by chronic treatment with an inhibitor of the Src kinase signaling pathway or an antagonist of the LDL receptors, but not by inhibitors of another class of Reelin receptor belonging to the integrin family. Consistent with these results, immunocytochemistry revealed that NR1-expressing neurons also expressed ApoER2 and VLDLR. These data reveal a new role for Reelin and LDL receptors and reinforce the idea of a prominent role of extracellular matrix proteins in postnatal maturation.