Effect of acute ethanol administration and acute allopregnanolone administration on spontaneous hippocampal pyramidal cell neural activity

We investigated the effect of acute ethanol administration and acute allopregnanolone administration on spontaneous hippocampal pyramidal cell neural activity. Both agents produced significant reductions in spontaneous firing rate of hippocampal pyramidal neurons at a medium and high doses. Furthermore, blockade of allopregnanolone biosynthesis by preadministration of finasteride, a 5alpha-reductase blocker, prevented ethanol-induced inhibition on hippocampal pyramidal neural activity. The results further demonstrate similar effects of allopregnanolone and ethanol on hippocampal neurophysiology and that allopregnanolone plays a key role in producing ethanol-induced inhibition of hippocampal neural activity.