The costs of coping: Different strategies to deal with social defeat stress might come with distinct immunologic, neuroplastic, and oxidative stress consequences in male Wistar rats.

Abstract

The impact of stress on health and well-being is determined by the ability of an individual to cope with challenges imposed by the stressor. Animals exposed to social defeat stress show different patterns of response during confrontations, leading to distinct stress-induced consequences. Using an established resident-intruder paradigm, we explored the outcomes of adopting active or passive coping strategies during a social defeat protocol over peripheral and central nervous system (CNS) levels of inflammatory cytokines, growth factors, glucocorticoid, and oxidative stress markers in male Wistar rats Animals that presented short latency to assume a defeated posture during confrontation considered as susceptible to stress-exhibited increased levels of brain-derived neurotrophic factor (BDNF) in the amygdala (AMY) and in the bed nucleus of the stria terminalis (BNST), and decreased lipid peroxidation in the CNS, suggesting changes in antioxidative defenses as well as stress-induced neuroadaptations. On the other hand, animals with longer latencies to assume a submissive posture consideredto be resilient to stress presented lower levels of CNS BDNF compared to short-latency animals and decreased enzymatic antioxidant defenses in the CNS in comparison to controls, which might indicate an increased risk of central oxidative damage. From the results, behavioral reactivity cannot be considered a predictor of success in responding to stress; however, the findings of this study reinforce the idea that exposure to stress has no predetermined negative effects.