BRAIN-DERIVED NEUROTROPHIC FACTOR INDUCTION OF N-METHYL-D-ASPARTATE RECEPTOR SUBUNIT NR2A EXPRESSION IN CULTURED RAT CORTICAL-NEURONS

N-methyl-D-aspartate (NMDA) receptor subunit expression changes during development and following injury in several brain regions. These chan ges may be mediated by neurotrophic factors, such as brain derived neu rotrophic factor (BDNF). Exposure of cultured cortical neurons to BDNF (100 ng/ml) for 24 h produced a significant decrease in the NMDA-indu ced whole-cell currents sensitive to the NR2B subunit selective NMDA r eceptor antagonist, CP-101,606, suggesting a relative decrease in NR2B subunit expression. There was a significant increase in NR2A by Weste rn blot analysis. Consistent with the electrophysiology and Western bl ot analysis, reverse transcriptase-polymerase chain reaction (RT-PCR) amplification revealed that BDNF caused a significant increase in rela tive NR2A subunit expression, a significant decrease in relative NR2B subunit expression and no change in relative NR2C subunit expression. These results suggest that BDNF enhances NMDA receptor maturation, war ranting further study of the mechanism of BDNF effects on NMDA recepto r subunit expression and the role these effects play in development an d neuronal injury. (C) 1998 Elsevier Science Ireland Ltd. All rights r eserved.