Early Postnatal Ethanol Exposure Has Long-Term Behavioral Consequences in Female Mice

Background/Objectives: Fetal alcohol spectrum disorders (FASDs) occur in nearly 5% of children in the United States and have been associated with alterations in neurological functions, neuroanatomical changes, and behavioral deficits encompassing an individual's lifetime. Alterations in myelination have been reported in both rodent models and humans. The cerebellum is a heavily myelinated brain region, and oligodendrocyte and myelination transcripts have been reported to be altered in the cerebellum following early-life ethanol (EtOH) exposure in a mouse model. In this study, we investigated cerebellar-recruited behaviors in adult female mice that were exposed to EtOH from postnatal day (P) 4 to P9. We investigated whether changes in oligodendrocyte lineage markers were present in adulthood. Methods: C57BL/6J offspring received a total of 5.0 g/kg/day of either ethanol (EtOH) or saline in two separate doses delivered subcutaneously two hours apart from P4 to P9. On P21, offspring were weaned and housed with same-sex littermates throughout the duration of the study. From P60 to P90, females underwent behavioral testing including an open field test (OFT), rotarod, and balance beam. Behavior naïve littermates were euthanized on P105, and cerebella were collected for qPCR to assess oligodendrocyte lineage transcripts. Results: We reported that, following EtOH exposure from P4 to P9, adult female mice had increased ambulatory behaviors in the OFT and subtle changes in behavior in the rotarod and balance beam compared to saline-exposed controls. Despite the behavioral changes observed in adulthood, we found that alterations in oligodendrocyte lineage transcripts present on P10 did not persist into adulthood. Conclusions: Subcutaneous injection of EtOH from P4 to P9 resulted in long-term consequences in locomotor and cerebellar-recruited behaviors in female mice.