Department of Psychobiology, Facultad de Psicología, Universitat de Valencia, Valencia, Spain.
Eur J Neurosci. 2018 Nov;48(9):2948-2970. doi: 10.1111/ejn.14127. Epub 2018 Sep 17.
Social interaction is known to be the main source of stress in human beings, which explains the translational importance of this research in animals. Evidence reported over the last decade has revealed that, when exposed to social defeat experiences (brief episodes of social confrontations during adolescence and adulthood), the rodent brain undergoes remodeling and functional modifications, which in turn lead to an increase in the rewarding and reinstating effects of different drugs of abuse. The mechanisms by which social stress cause changes in the brain and behavior are unknown, and so the objective of this review is to contemplate how social defeat stress induces long-lasting consequences that modify the reward system. First of all, we will describe the most characteristic results of the short- and long-term consequences of social defeat stress on the rewarding effects of drugs of abuse such as psychostimulants and alcohol. Secondly, and throughout the review, we will carefully assess the neurobiological mechanisms underlying these effects, including changes in the dopaminergic system, corticotrophin releasing factor signaling, epigenetic modifications and the neuroinflammatory response. To conclude, we will consider the advantages and disadvantages and the translational value of the social defeat stress model, and will discuss challenges and future directions.
社会交往是人类压力的主要来源，这解释了这项在动物身上开展的研究具有重要的转化意义。过去十年的证据表明，当动物经历社会挫败经历（青春期和成年期短暂的社会对抗事件）时，啮齿动物大脑会发生重塑和功能改变，进而导致不同滥用药物的奖赏和强化作用增加。社会压力导致大脑和行为发生变化的机制尚不清楚，因此，本综述的目的是思考社会挫败压力如何引起持久的后果，从而改变奖励系统。首先，我们将描述社会挫败压力对滥用药物（如精神兴奋剂和酒精）奖赏作用的短期和长期后果的最典型结果。其次，在整个综述中，我们将仔细评估这些影响背后的神经生物学机制，包括多巴胺能系统、促肾上腺皮质激素释放因子信号、表观遗传修饰和神经炎症反应的变化。最后，我们将考虑社会挫败压力模型的优缺点和转化价值，并讨论挑战和未来方向。
