Postnatal developmental changes in AMPA and NMDA receptors in the rat vestibular nuclei

Changes in the expression of the AMPA receptor subunits GluR1-4 and of the NMDA receptor subunits NR1, NR2A-D were investigated in the developing rat medial and lateral vestibular nuclei. Analyses were performed using nonradi oactive in situ hybridization and immunoblotting with subunit-specific anti bodies. During the postnatal development, glutamatergic receptor subunits w ere differentially expressed in the vestibular nuclei. The level of express ion of GluR1, GluR4 and NR1 subunits was higher in the developing brain as compared to the adult. We observed a gradual increase in GLuR2/3, NR2A, NR2 B and NR2C levels of expression in the medial and lateral vestibular nuclei during the first 3 weeks of postnatal development. In situ hybridization r esults were consistent with immunoblot analyses. The differential expressio n of AMPA and NMDA receptor subunits in immature vestibular neurons is cons istent with changes in glutamate receptor properties. This may be related t o the postsynaptic regulation of receptor subunits associated with the syna ptic plasticity of the vestibular neuron connections during specific sequen ces of postnatal development. (C) 2000 Elsevier Science BTV. All rights res erved.