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

Chronic exposure to ethanol leads to adaptive responses in neurons, includi ng enhanced activity of N-methyl-D-aspartate (NMDA) receptors. Chronic trea tment 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 cause d enhanced transcription of the genes for the glutamate-binding (GBP) and g lycine-binding protein subunits of the receptor-like complex. This treatmen t had no effect on protein turnover of either GBP or of the NMDA receptor s ubunit NR1, suggesting that the increases in protein expression are the res ult of increased DNA transcription. (C) 2001 Published by Elsevier Science Ireland Ltd.