Chronic ethanol exposure increases gene transcription of subunits of an N-methyl-D-aspartate receptor-like complex in cortical neurons in culture.

Abstract : Chronic exposure to ethanol leads to adaptive responses in neurons, including enhanced activity of N-methyl-D-aspartate (NMDA) receptors. Chronic treatment of neurons with ethanol also leads to increases in the protein levels of three subunits of an NMDA receptor-like complex. In the present study, we explored whether the increases in subunit protein levels are the result of either increased transcription or diminished protein turnover. We found that a 72-h exposure of cortical neurons in culture to 100 mM ethanol caused enhanced transcription of the genes for the glutamate-binding (GBP) and glycine-binding protein subunits of the receptor-like complex. This treatment had no effect on protein turnover of either GBP or of the NMDA receptor subunit NR1, suggesting that the increases in protein expression are the result of increased DNA transcription.