Prenatal Association between a Chemosensory Cue (Cineole) and Ethanol Postabsortive Effects Modulates Later Operant Responsiveness to Cineole-Flavored Milk in 1 Day Old Rats

Near-term rat fetuses detect and associate ethanol’s sensory and postabsortive properties. We aimed to evaluate changes upon operant conditioning in neonates, as a function of prenatal ethanol-mediated associative experiences. Prenatal treatments were: Paired group, dams administered (i.g.) with cineole and 15-min later with EtOH (2.0 g/kg); Long-delay group, dams received cineole 6 hours before ethanol intoxication; Water group, dams received two administrations of water separated by 15 min. On PD1 neonates were trained in an operant task. Two different learning conditions were used. Paired pups were trained under a FR=1 reinforcement schedule. Yoked pups received the reinforcer but, unrelated to their own behavior. Milk or Cineole-flavored milk were the reinforce solutions. Present results support the idea that ethanol-related prenatal memories modulate operant responsiveness when pups are re-exposed to cues that predict toxic consequences of the drug.