Early-life stress due to infant maltreatment reshapes reactivity to stress in adult rats.

JAZMIN GRILLO BALBOA; AILÉN A. COLAPIETRO; VERONICA CANTARELLI; MARINA PONZIO; MARIA EUGENIA PALLARES; CHERTOFF MARIELA; MARTA ANTONELLI

Congreso; XXXVIII Congreso de la Sociedad Argentina de Investigación en Neurociencias; 2023

Sociedad Argentina de Investigación en Neurociencias

Early parental care is crucial for the proper development of the cortico-limbic circuits regulating the stress response and emotional well-being. Thus, infant maltreatment may lead to mood-related disorders, impairing individuals? capacity to deal with stress. Here, we employed the ?Scarcity-adversity model? (SAM) in rats −limiting the nes ting resources during postnatal days (PND) 8-12− and studied its impact on maternal and adult offspring?s behavior. While the SAM did not affect dam weight gain or fecal corticosterone metabolites, we did find a heightened maternal anxiety-like phenotype in the Elevated plus maze (EPM), shown by a reduced tendency to explore the open arms. Adult offspring underwent a series of anxiogenic tests to assess their reactivity to stress. SAM males showed a decreased locomotor activity in the Open field test; and an earlier, more prolonged time in immobility in the Forced swim test. SAM rats of both sexes exhibited an increased open-arm latency, lower closed-arm latency, and a tendency to decrease their risk-assessment behaviors in the EPM. These results suggest that the SAM protocol induces lasting alterations in the risk-taking behavior, reactivity to novelty and to acute stressors in rodents, with males being more vulnerable than females. Our findings underpin the crucial role of a nurturing early-life environment in fostering both mental and physical well-being later in life, thereby reducing the risk of psychopathology.