| Abstrakt: |
Introduction: Early life adversity as an important environmental factor in interaction with genotype have been suggested to shape individual variability to develop stress related psychopathologies in chronic exposure to subsequent stressors. This is the first work to study the effects of maternal separation (MS) stress on the co-occurrence of depression and cognitive impairments under chronic social defeat stress (CSDS) in young adult male rats. Methods and Materials: During the first two postnatal weeks, the male pups were either exposed to MS or left undisturbed with their mothers (Std). Subsequently, starting on postnatal day 50 (PND50), the animals of each group were either left undisturbed in the standard group housing (Con) or underwent CSDS for three weeks. Totally, there were four groups (n=10/group), namely Std-Con, Ms-Con, Std-CSDS, and MS-CSD. Pup retrieval test was performed for 60 min on daily basis from PND1 to PND14 to evaluate dam-pup interactions. During the last week of the CSDS exposure, in the light phase, the behavioral tests and the retro-orbital blood sampling were performed to assess basal plasma corticosterone levels. Results: Exposure to CSDS increased the basal plasma corticosterone levels and induced social avoidance along with memory deficit. Maternal separation intensified the plasma corticosterone levels in response to CSDS. Meanwhile, it facilitated the spatial learning and potentiated resilience to social avoidance and memory deficit. Performance in the pup retrieval test revealed a significant increase in maternal care scores among the MS dam group than undisturbed dams. Conclusion: Although maternal separation increased the basal plasma corticosterone levels, it could facilitate the learning process and induce resilience to the onset of depression and memory deficit in response to CSDS, probably through the compensatory increase in maternal care. [ABSTRACT FROM AUTHOR] |
