Enhancement of NMDA receptor maturation by BDNF in cultured mouse cerebellar granule cells.

The N-methyl-D-aspartate (NMDA) subtype of glutamate receptor, which is essential during organogenesis for neuronal differentiation and formation of synaptic connections in the developing brain, changes its receptor properties during development by differential expression of multiple subunits. Using a combined electrophysiological and pharmacological approach on primary cultures of mouse cerebellar neurones, we investigated the evolution of the NMDA receptor and the potential effect of the neurotrophin BDNF on its expression. We showed that 1) the current density of NMDA responses increased with time of culture; 2) epsilon 1 subunit expression increased with time in culture relative to epsilon 2 subunit expression; and 3) the time course of the increase in NMDA responses was accelerated by about 2 days in the presence of BDNF.