Prenatal cocaine exposure alters maternal retrieval behavior in mice

Previous studies have demonstrated alterations in maternal retrieval behavior as a result of direct cocaine exposure. To establish the influence of prenatal cocaine exposure on pup retrieval, we exposed pups of three F₁ genotypes by injecting their mothers (all C57BL/10J strain) with 20 mg/kg cocaine hydrochloride or saline subcutaneously on gestation days 7 to 17. When those pups became adults, control and exposed females were mated with males of the same genotype and tested for pup retrieval on postpartum days 4 and 5. Because ultrasonic calls are known to be elicitors of maternal retrieval behavior, the rate of ultrasonic calling was measured. Prenatal cocaine exposure exerted a significant effect upon retrieval latency on day 4. No relationship was found between genotype and retrieval latency.