Behavioral phenotypic outcomes in juvenile rats following infant maltreatment

JAZMIN GRILLO BALBOA; VERONICA PASTOR; AILEN COLAPIETRO; MARIA EUGENIA PALLARES; MARTA C ANTONELLI

Congreso; XXXV Reunión Anual de la Sociedad Argentina de Investigación en Nuerociencias; 2020

Early-life stress (ELS) increases the propensity to develop psychopathologies later in life. Much of the evidence regarding the effects of ELS focuses on adults, leaving younger ages unexplored. Because in human scenarios of ELS the mother is present but her behavior is abnormal, an ELS naturalistic rodent model is desirable for translational studies. Here we examine the phenotypic outcomes of juvenile Wistar rats exposed to the scarcity-adversity model (SAM) of low nesting resources, which elicits adverse caregiving conditions (e.g.: maltreatment) toward neonates. SAM was performed from postnatal day (PND) 8-12, a critical period for the development of brain structures related to stress and emotional regulation in pups. Male and female offspring at PND 25-29 were evaluated in the open-field and forced swimming test for anxiety-/depressive-like behaviors. Mothers from the SAM condition showed increased violent conducts toward their pups and a fragmented behavior. SAM offspring revealed greater exploratory behaviors, while a lessened anxious-like behavior was only evident in males. Conversely, depressive-like behaviors were higher in males compared to females. Our results show that exposure to a violent and unpredictable perinatal environment has sex-specific consequences on juvenile offspring?s behavior. Further study of the neurobehavioral phenotype of SAM-reared individuals could be key to understanding the early onset of ELS-related psychopathologies.