Effects of 24-h maternal deprivation on the emotional memory and social behaviour of adult rats

• Grant number: 08/07448-9
• Support Opportunities: Scholarships in Brazil - Master
• Start date: September 01, 2009
• End date: February 28, 2011
• Field of knowledge: Biological Sciences - Pharmacology - Neuropsychopharmacology
• Principal Investigator: Deborah Suchecki
• Grantee: Viviane Côrtes Ceschim
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil

Abstract

Among the numerous strategies available for investigation of the effects of early life stressful experiences in rats, one consists of the deprivation of rat pups from their mothers for 24h, during the neonatal period. The development of the stress response is characterized by hyporesponsiveness of the hypothalamic-pituitary-adrenal (HPA) axis, which is essential for the development and maturation of the central nervous system and is regulated by maternal presence. Maternal deprivation (MD) for 24h between postnatal days (PND) 3 and 4 results in stress hyperesponsiveness in adulthood, whereas the same manipulation between PND 11 and 12 results in hyporesponsiveness. Trauma during childhood and/or adolescence are risk factors for the development of posttraumatic stress disorder (PTSD), a psychiatric disorder characterized by reexperience of the traumatic event, and difficulty to extinguish the traumatic memory. PTSD patients present hyperactivation of the sympathetic-adrenal axis associated with hypofunctional HPA axis, being norepinephrine an important mediator of the increased emotional memory. Moreover, PTSD patients commonly exhibit reduction of social interaction. Therefore, the aim of this study is to evaluate how early adverse experiences (maternal deprivation during the neonatal period and inescapable intense shock during adolescence) interact in order to change the animal vulnerability to the development of PTSD-like behaviour in rats. Thus, behaviours associated to stress, such as emotional memory and social behaviour, will be assessed in an attempt to extend previous findings for the development of an experimental model of PTSD. The idea of this project originates from a proposal financed by this agency in which the results show an increase in anxious behavior in male and female rats. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

CESCHIM, VIVIANE C.; SUMARAN, PAULA; BORGES, ANDREA A.; GIRARDI, CARLOS EDUARDO N.; SUCHECKI, DEBORAH. Maternal deprivation during early infancy in rats increases oxytocin immunoreactivity in females and corticosterone reactivity to a social test in both sexes without changing emotional behaviour. Hormones and Behavior, v. 129, MAR 2021. (14/13454-2, 08/07448-9, 15/26364-4)