0263 Effects of Prenatal Sleep Restriction on Maternal Behavior in Female Rats

Abstract

Abstract Clinical data have suggested the relationship between sleep disruption during pregnancy and postpartum depression. Consequently, preclinical studies evaluating the effects of gestational sleep deprivation on maternal behavior are needed in order to provide more details on the background mechanisms underlying this relationship and to promote a better understanding of it under an ethological perspective. Thirty-two female 90 days-old Wistar-Hannover rats were distributed in 2 groups: Control group (CTRL - n=13), not subjected to any manipulation during pregnancy; and sleep restriction group (SR - n=19) - subjected to sleep restriction during the whole pregnancy (21 days). Maternal behavioral analysis was conducted from postpartum day 1 (PPD1) to PPD7, based on observational ethograms. On PPD11 the animals were subjected to a self-grooming analysis by means of the grooming analysis algorithm, followed by behavioral testing on the elevated plus maze. On initial uncontrolled ethogram-based analysis, an increased in self-grooming was observed among sleep-deprived rats, but no significant differences were found in maternal behavior. Controlled analysis, balanced for potential confounding factors, detected an impairment in high-arched back nursing in sleep-deprived animals. The grooming microstructure analysis, performed on PPD11, showed a reduced frequency of incorrect transitions on the sleep restricted animals, denoting reduced anxiety. No significant differences were observed in the elevated-plus maze. Female rats sleep-restricted during pregnancy display an equivalent or slightly modified behavior during the postpartum period, when compared to animals not submitted to any stressful factor, concomitantly with a decrease in anxiety-like behavior parameters. This behavioral maintenance is mediated by adaptive mechanisms, which are tailored to assure the viability and survival of the litter. These effects probably happened due to an inhibition of both anxiety-like behavior and stress responses. Thus, results suggests that anxiolysis is an adaptive mechanism to allow the lactating females to perform maternal behavior in adequate levels, even in face of a stressful factor such as prenatal sleep-deprivation. AFIP, CNPq and FAPESP.