0297 Exploring sex and strain differences in mouse models of sleep disruption

Abstract

Abstract Introduction Sleep abnormalities are a common feature of neurodevelopmental disorders (NDDs), and can have severe consequences for the affected individual and their families. Although mouse models can be used to investigate the mechanistic basis for social deficits and other symptoms of NDDs, recapitulating sleep phenotypes in mice has proven to be difficult. In this study, we determined whether a sleep-disruption challenge could reveal or exacerbate sex and strain differences in sleep patterns, using two well-validated mouse models of autism-like behavior; the BALB/cByJ and C58/J inbred strains. Methods Mice were placed in a piezoelectric sleep system for 3 days to evaluate baseline sleep rhythms. Mice were then exposed to a series of novel environments, including open field boxes and activity wheel cages, for 3 hours during the morning period of the light cycle. Sleep rebound was determined by comparing percent time spent sleeping and average sleep bout length in the three 6-hr intervals before and after the sleep disruption. Subjects were males and females of the C57BL/6J, BALB/cByJ and C58/J strains. Results At baseline, the C57BL/6J and BALB/cByJ females showed significantly reduced percent sleep, in comparison to males. During rebound from sleep disruption, BALB/cByJ mice had higher percent time and longer sleep bouts than C57BL/6J, suggesting a greater vulnerability to the effects of sleep disruption. Additionally, female C58/J mice lacked the highly robust increase in percent sleep seen in C57BL/6J in the early night interval after sleep disruption. Conclusion Overall, the data provide evidence that this sleep disturbance procedure can induce a sleep rebound effect, which could be helpful in revealing strain and sex differences in NDD mouse models. Support (If Any)