Neurobehavior effects in four strains of mice offspring exposed prenatally to alprazolam

Objective: This study was performed to determine whether prenatal exposure to alprazolam affects offspring behavior in different strains of mice. Study Design: Eight to 11 gravid mice of the C3H/He, C57BL/6, A/J, and DBA/2 strains were given either an anxiolytic dose of alprazolam (0.32 mg/kg) or a placebo by gavage on day 18 of an anticipated 19- to 21-day gestation. Neurobehavior tasks were conducted to assess anxiety, learning and memory, and social interaction. Data were analyzed by analysis of variance or a Fisher exact probability test. Results: Anxiety in alprazolam-exposed offspring was reduced in C3H/He (P< .05) and A/J (P< .05) newborn infants by separation vocalization but may be increased in the C3H/He adult strain on the plus maze task. Learning was slower among C57BL/6 mice exposed to alprazolam (P< .01), whereas memory was reduced in exposed A/J and DBA/2 offspring (P< .05). Alprazolam exposure was associated with more aggression among C3H/He and C57BL/6 male offspring (P< .01) and with less group activity by C57BL/6 offspring (P< .05). Conclusion: Altered behaviors in several mouse strains after prenatal exposure to alprazolam suggests a vulnerability of GABA-benozdiazepine receptor formation in fetal brain development. (Am J Obstet Gynecol 2002;187:968-72.)