Electrophysiology of hippocampal CA1 neurons after prenatal ethanol exposure

In the present study, we examined the longitudinal effects of prenatal etha nol exposure on the electrophysiological characteristics of CAL neurons in hippocampal slices. Hippocampal slices were obtained from young (25-32-day old) and adult (63-77-day old) male offspring of rats given one of four tre atments during gestation. Three groups of pregnant rats were orally intubat ed with 0, 4, or 6 g/kg ethanol on gestational days 8-20. Caloric intake fo r the 0- (nutritional control) and 4-g/kg groups was yoked to that of the 6 g/kg group. A fourth group (untreated control) was not intubated, and was given ad lib access to food. Long-term potentiation and paired-pulse inhibi tion were unaffected by prenatal ethanol exposure in young and adult rats; however, slices taken from the young 6 g/kg ethanol group displayed a signi ficantly lower maximal CA1 population spike amplitude evoked by Schaffer co llateral stimulation as compared to young controls. This difference was not observed in adult animals. These data suggest that some aspects of hippoca mpal physiology are negatively affected in young rats as a result of prenat al ethanol exposure, but this effect reverses as the animal matures. (C) 19 99 Elsevier Science Inc. All rights reserved.