Development
Author: Rocío Beatriz Foltran | Email: rociobfoltran@gmail.com
Rocío B Foltran1°, Carla V Argañaraz1°,Mariano Soiza-Reilly1°
1° Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE) UBA-CONICET. Buenos Aires, Argentina
Early-life stress elicits anxiety and depressive-like behaviors both in humans and in rodents. At the same time, low levels of serotonin have been linked to the origin of these mental disorders, and drugs enhancing brain serotonin levels are the first line treatment for these neuropsychiatric conditions. Here we sought to investigate the role of serotonin in a maternal separation model of early-life stress in mice. C57BL/6 pups were subjected to the maternal separation (MS) protocol (3h/day) during a postnatal critical period (P2-P14) while receiving daily injections of the tryptophan hydroxylase inhibitor para-chlorophenylalanine (PCPA, 10mg/kg/day s.c.). Then in adulthood (from P80) we performed the Open Field (OF), Elevated Plus Maze, Sucrose Splash, Novelty Suppressed Feeding (NSF) and Forced Swimming tests to study emotional behavior. PCPA-treated mice had lower weight gain throughout the entire treatment period, which was restored by P25. In the MS model, male mice were more susceptible and showed higher levels of anxiety. PCPA treatment had synergistic effects with MS in females, were stress had milder effects that became apparent only when serotonin was depleted. Our results emphasize the emotional alteration following early life stress and its interaction with the serotonin system, in the search for understanding one of the main risk factors for the development of psychiatric disorders.