Blood ethanol concentration from early postnatal exposure: effects on memory-based learning and hippocampal neuroanatomy in infant and adult rats.

Early postnatal exposure to ethanol (EtOH) that results in daily high-peak blood ethanol concentration (BEC) retarded the acquisition of single-patterned alteration (PA), a kind of memory-based discrimination learning, and was related to reduced brain weight, hippocampal cell number, and CA1 area in infant rats. These behavioral and neuroanatomical effects survived into young adulthood. On the PA discrimination, in both pups and young adults, postnatal exposure to high-peak EtOH condition, in relation to low-peak and control conditions, impaired the acquisition of PA at 60-s but not at 30-s intertrial intervals. These results provide further evidence of hippocampal involvement in intermediate-term memory and indicate that early postnatal EtOH is a behavioral and neuroanatomical teratogen, particularly when the BEC is relatively high.