During adolescence the brain has a greater sensitivity to the influence of external stimuli. In particular, animal studies have demonstrated that both ethanol (EtOH) and noise can cause damage to the hippocampus (HC), a brain region associated with memory and anxiety-related behaviors. However, there is limited information regarding the effects of noise on female rats. Thus, the aim of this work was to examine the effects of EtOH and noise exposure on HC-related behaviors in adolescent female rats.

Female Wistar rats (28-days-old) were subjected to a two-bottle choice intermittent EtOH intake paradigm for 4 weeks. Additionally, during the 6th and 9th drinking sessions, a subgroup of rats was exposed to noise (95-97 dB, 2h). Finally, Open Field, Elevated Plus Maze and Object Location tasks were performed.

The results revealed that noise exposure alone led to an increase in anxiety-like behaviors, while EtOH intake alone or in combination with noise decreased head dipping (a risk assessment behavior). Moreover, both stimuli separately or together resulted in decreased exploraty activity. However, no significant differences were observed in spatial and habituation memories.

These findings suggest that both exposure to noise and EtOH during adolescence can cause changes in HC-related behaviors of female rats. First, the fact that EtOH intake promotes lower exploration and risk assessment behaviors could be dangerous since it implies less caution and greater exposure to potential dangers. Second, increased anxious behavior and decreased exploration of the environment, as observed in noise-exposed rats, could result maladaptive. Finally, the combination of both stimuli does not generate greater behavioral changes than those observed in rats that only consumed EtOH. These findings might resemble some of the behavioral alterations in human adolescents, resulting in an appropriate animal model to further investigate the mechanisms involved in the hippocampal-related behavioral altera