EXPRESSION OF N-METHYL-D-ASPARTATE RECEPTOR SUBUNIT MESSENGER-RNAS INTHE RAT PHEOCHROMOCYTOMA CELL-LINE PC12

The expression of the N-methyl-D-aspartate (NMDA) receptor subunit mRN As NMDAR1 and NMDAR2A-D was characterized in undifferentiated and nerv e growth factor (NGF)-differentiated PC12 cells using Northern blottin g, RNase protection assays (RPA) and polymerase chain reaction (PCR). PC12 cells expressed predominately the splice variant NMDAR1-4a and sm aller amounts of NMDAR1-1a, NMDAR1-2a and NMDAR1-3a. No splice isoform s containing exon 5 were detected. The NMDAR2C subunit was detected in PC12 cells by Northern blotting and trace amounts of NMDAR2A, B and D were detected by PCR. PC12 cells may be a useful model system for the study of the transcriptional and post-transcriptional regulation of e xpression of the NMDA receptor subunit genes, including the alternativ e splicing of NMDAR1 pre-mRNAs.