Efeitos da privação de sono REM e da exposição ao etanol durante o desenvolvimento no comportamento de camundongos pré-púberes no teste de nado forçado

Abstract

The consumption of alcoholic beverages during pregnancy is responsible for a series of neurobehavioral disorders associated with Fetal Alcohol Spectrum Disorder (FASD) such as attention deficit hyperactivity disorder, learning and memory deficits and autism spectrum disorder. Despite the large number of studies, the mechanisms involved with the manifestation of these disorders remain elusive. Some studies suggest that sleep disorders may have a relevant role in the manifestation of neurobehavioral deficits observed in FASD. This study was designed to evaluate whether sleep deprivation at a juvenile age aggravates the neurobehavioral disorders caused by developmental exposure to ethanol. Swiss mice were submitted to intraperitoneal injections of 0.5 μl/g of ethanol (ETOH group) or saline solution (SALINE group) on alternate days between PN2 and PN8 (PN1 = birth day) or were not manipulated from PN2 to PN8 (NORMAL group). From PN23 to PN25, mice were submitted to REM sleep deprivation by the modified method of the multiple platform (DEPRIVATE group) or to control procedures (CONTROL group) or remained in their breeding cages (NAÏVE group). In PN35, the swimming activity was evaluated in the forced swim test at 1-min time intervals for 5 minutes. Both sleep deprivation and exposure to ethanol promoted an increase in swimming activity. However, analysis of behavior over time intervals suggests that hyperactivity induced by sleep deprivation and exposure to ethanol may be of a different nature. The DEPRIVATE group start the test with a locomotor activity greater than that of the NAIVE and CONTROL groups and this difference is maintained even with the reduction of activity over time. Mice of the ETOH group, on the other hand, begin the test with the same activity level as the NORMAL and SALINE groups, but have a lesser reduction in locomotor activity over the time intervals. It was not possible to identify a combined effect (synergistic or additive) of sleep deprivation and exposure to ethanol.