Hippocampal (HC)-related behavioral alterations induced by intermittent voluntary ethanol (ETOH) intake and noise exposure in adolescent female rats

SERRA, HA; MOLINA, SJ; BUJÁN, GE; GUELMAN, LR

Virtual (New Orleans, LA, cancelado por Coronavirus)

Congreso; ISBRA/RSA 2020 Conference; 2020

Research Society on Alcoholism (RSOA)

Adolescence is a critical stage in Central Nervous System maturation, in which different biochemical and neurotransmission changes might underlie the appearance of behavioral characteristics. EtOH intake in the presence of high noise intensities is prevalent in human adolescence. Animal studies have shown that both stimuli presented separately might have detrimental effects on animal behavior. Therefore, the aim of the present work was to investigate the effects of EtOH and noise present together on HC-related behavioral parameters in adolescent animals.Female Wistar rats at early adolescence (28-days-old) were subjected to voluntary ethanol consumption for intermittent periods of 24 hours for two weeks, using the two-bottle choice paradigm (5% EtOH/1% sucrose). A subgroup was exposed to noise (2 h, 95?97 dB) after the first week. All animals were evaluated in different behavioral tasks, including open field (OF), elevated plus maze (EPM) and inhibitory avoidance (IA). The amount of EtOH ingested was also recorded.Results showed that noise exposure was able to decrease associative memory (AM, ratio in the IA task, T2/T1: sham: 118.6 28.52; noise: 46.02 34.36) and to increase anxiety-like behaviors (Anx, latency to open arms in EPM task: sham: 11.25 6.07; noise: 14 2.8), as well as risk assessment behaviors (sham: 29.17 5.89; noise: 83.89 4.80) when compared with sham animals. In contrast, although animals subjected to EtOH intake exhibited also a decrease in AM (T2/T1: EtOH: 46.79 13.46), Anx were decreased (entries to center of the OF: sham: 6.20 2.28; EtOH: 10.86 4.05) when compared with sham rats. Finally, when noise exposure was interposed between the two weeks of EtOH intake, no changes were observed in either parameter. In addition, animals exposed to both agents consumed less amount of EtOH than those subjected to EtOH intake alone (70% of EtOH values).In conclusion, these findings suggest that an introduction of an episode of noise exposure between two periods of intermittent EtOH intake could trigger compensatory mechanisms that might interfere with the machinery that underlie the behavioral alterations induced, probably due to the lower amount of EtOH ingested in each session. Finally, it could be proposed that adolescence represents a period of great vulnerability to physical and chemical agents that can interact to achieve a more adaptive behavioral output.