BACKGROUND Chronic social defeat stress induces depression and anxiety-like behaviors in rodents and also responsible for differentiating defeated animals into stress susceptible and resilient groups. The present study investigated the effects of social defeat stress on a variety of behavioral parameters like social behavior, spatial learning and memory and anxiety like behaviors. Additionally, the levels of various dopaminergic markers, including the long and short form of the D2 receptor, and total and phosphorylated dopamine and cyclic adenosine 3',5'-monophosphate regulated phosphoprotein-32, and proteins involved in intracellular trafficking were assessed in several key brain regions in young adult mice. METHODS Mouse model of chronic social defeat was established by resident-intruder paradigm, and to evaluate the effect of chronic social defeat, mice were subjected to behavioral tests like spontaneous locomotor activity, elevated plus maze (EPM), social interaction and Morris water maze tests. RESULTS Mice were divided into susceptible and unsusceptible groups after 10 days of social defeat stress. The susceptible group exhibited greater decreases in time spent in the open and closed arms compared to the control group on the EPM. In the social interaction test, the susceptible group showed greater increases in submissive and neutral behaviors and greater decreases in social behaviors relative to baseline compared to the control group. Furthermore, increased expression of D2L, D2S, Rab4, and G protein-coupled receptor associated sorting protein-1 was observed in the amygdala of the susceptible group compared to the control group. CONCLUSION These findings suggest that social defeat stress induce anxiety-like and altered social interacting behaviors, and changes in dopaminergic markers and intracellular trafficking-related proteins.

中文翻译：

---

社会失败压力对多巴胺D2受体亚型和参与细胞内运输的蛋白质的影响。

背景技术慢性社交挫败压力在啮齿动物中引起抑郁和焦虑样行为，并且还负责将被击败的动物区分为压力敏感和有弹性的群体。本研究调查了社交挫败压力对各种行为参数（如社交行为，空间学习和记忆以及焦虑样行为）的影响。此外，还评估了多种多巴胺能标记物的水平，包括长短形式的D2受体，总和磷酸化多巴胺和环状腺苷3'，5'-单磷酸调节的磷蛋白-32，以及参与细胞内运输的蛋白质。成年小鼠的关键大脑区域。方法采用常驻入侵者模式建立慢性社交失败的小鼠模型，为了评估慢性社交失败的影响，对小鼠进行了行为测试，例如自发运动能力，高架迷宫（EPM），社交互动和莫里斯水迷宫测试。结果经过10天的社交挫败压力后，小鼠被分为易感和不易感组。与EPM上的对照组相比，易感组在张开和闭合臂上花费的时间减少更大。在社交互动测试中，与正常对照组相比，易感人群表现出顺从和中立行为增加更多，社交行为减少幅度更大。此外，与对照组相比，在易感组的杏仁核中观察到D2L，D2S，Rab4和G蛋白偶联受体相关分选蛋白-1的表达增加。