Age- and sex- dependent effects of moderate gestational day 12 prenatal alcohol exposure on anxiety-like behaviors, ethanol intake, and mechanical sensitivity.

RATIONALE: Prenatal alcohol exposure (PAE) can result in Fetal Alcohol Spectrum Disorder (FASD), which consists of a group of diagnosable medical conditions that can include an increased risk for anxiety disorders and/or alcohol misuse, and sensory issues, such as increased mechanical sensitivity.

OBJECTIVE

This study investigated how a single moderate PAE on gestational day 12 (G12) alters anxiety-like behavior, ethanol (EtOH) intake, and mechanical sensitivity across the lifespan of Sprague Dawley rats.

METHODS

Pregnant dams were exposed to vaporized EtOH or room air (control) for 6 hours (BECs ~108 mg/dL). Testing in male and female offspring began at three different ages: juveniles (~postnatal day (P) 25), adolescents (~P45) and adults (~P80).

RESULTS

The greatest PAE effects were observed in adolescent animals, with alterations in anxiety-like behaviors demonstrated in the light-dark box and elevated plus maze. Additionally, adolescent female animals consumed more sweetened EtOH compared to males. However, PAE adolescent animals consuming less sweetened EtOH compared to their counterparts, which was also observed in adult PAE females. Interestingly, this effect is reversed in juvenile and adolescent males when tested with unsweetened EtOH, with juvenile females consuming more EtOH also. Finally, PAE and air animals exhibited increased mechanical sensitivity following post-natal EtOH consumption across all ages.

CONCLUSION

These data demonstrate that there are age- and sex-specific effects of PAE on anxiety-like behaviors, EtOH intake, and mechanical sensitivity that are more distinct in adolescent animals.