V-047 | SEX-SPECIFIC CONSEQUENCES OF INFANT MALTREATMENT ON BEHAVIORAL AND PHYSIOLOGICAL REACTIVITY TO STRESS IN RATS

Cognition, Behavior, and Memory
Author: Jazmín Grillo Balboa | Email: jazmin.grillo28@gmail.com

Jazmín Grillo Balboa^1°, Ailén Alba Colapietro^2°,Verónica Cantarelli^3°, Marina Ponzio^3°, María Eugenia Pallarés^2°, Mariela Chertoff^1°, Marta Cristina Antonelli^2°

^1° Laboratorio de Neuroepigenética y Adversidades Tempranas, IQUIBICEN-DQB, Facultad de Ciencias Exactas y Naturales – Universidad de Buenos Aires – CONICET, Argentina.
^2° Laboratorio de Programación Perinatal del Neurodesarrollo, IBCN, Facultad de Medicina – Universidad de Buenos Aires, Argentina
^3° Instituto de Investigaciones en Ciencias de la Salud, Facultad de Ciencias Médicas – Universidad Nacional de Córdoba, Argentin

Parental care during infancy is crucial for developing cortico-limbic circuits that regulate stress and emotional health. Conversely, infant maltreatment can increase susceptibility to mood disorders and impair stress-coping abilities. Using the “Scarcity-Adversity Model” (SAM) in rats, which limits nesting resources from postnatal days 8 to 12, we studied its effects on maternal care and offspring stress reactivity and behavior. SAM-exposed mothers showed fragmented care and increased violence towards pups. By postpartum day (PPD) 13, maternal fecal corticosterone metabolites (FCM) were elevated, and at weaning (PPD21), SAM dams exhibited heightened anxiety-like behavior in the Elevated Plus Maze (EPM) test, with fewer entries into the open arms. In adulthood, SAM-exposed pups underwent anxiogenic tests. Male rats showed reduced locomotor activity in the Open Field test and increased immobility in the Forced Swim test. Both male and female SAM rats had increased latency to enter open arms and reduced risk-assessment behaviors in the EPM. Additionally, male SAM rats exposed to acute stress had lower FCM levels, matching their passive reactivity in behavioral tests.Our results confirm that SAM induces long-lasting changes in risk-taking behavior, responsiveness to novel stimuli, and stress reactions, especially in males. These findings highlight the importance of early-life nurturing in promoting well-being and reducing future psychopathological risk.