Mitigating effects of combined prenatal and postnatal exposure to ethanol on learned persistence in the weanling rat: a replication under high-peak conditions.

Replicating an earlier report under low-peak blood ethanol concentration (BEC) conditions, weanling rats, exposed in utero or postnatally to levels of ethanol that resulted in high-peak BECs, showed an attenuated partial reinforcement extinction effect, whereas pups exposed both pre- and postnatally did not differ from controls. Also supporting earlier work, postnatal exposure resulted in significantly reduced brain weight and had effects on hippocampal measures. These results from the combined-exposure group, along with earlier work, point to a possible mitigating influence in the rat of prenatal exposure to ethanol on the behavioral effects of postnatal exposure. They suggest that a protective factor may be operating, akin to the proactive immunoreactive effects of heat shock proteins shown in recent work at the cellular and hippocampal levels.