Impact of a single, intense prenatal stress on ethanol drinking behaviour and cognition in adult male rats

Abstract

Early exposure to stressful stimuli is crucial for developing varied behavioural patterns in adulthood such as anxiety, cognitive dysfunc tion and abuse disorders.1 The alteration of the hypothalamic–pitu itary-adrenal (HPA) axis represents the neurobiological substrate responsible of the behavioural consequences of prenatal stress (PS). Indeed, prenatal manipulation of the HPA axis impacts on cognitive performance of the adult offspring,2 but also on vulnerability to alcohol consumption.3 Prenatal acute, moderate restraint stress has proved to facilitate HPA axis development of the offspring, since maternal corti costerone secretion leads to the reduction of anxiogenic behaviour and an improvement in the ability to cope with stress, increasing both the rate of learning and long-term potentiation,4 but also gestational stress blunts initial alcohol-induced HPA axis activation. In our recent study, moderate alcohol intake proved to reduce emotionality and facil itate the adaptive responses to stress, enhancing behavioural flexibil ity.5 Based upon these findings, we aimed at assessing the impact of a single, intense prenatal stress on exposure to alcohol preference and on the effects exerted by ethanol on behavioural reactivity, anxiety-like behaviour and spatial learning in adult male Wistar rats.