Division of Social medicine, Department of Clinical Information Engineering, Graduate School of Medicine, University of Tokyo, Japan.
Laboratory for Systems Neurosciences & Preventive Medicine, Faculty of Human Sciences, Waseda University, Saitama, Japan.
FEBS J. 2018 Jan;285(1):188-196. doi: 10.1111/febs.14334. Epub 2017 Nov 29.
Social dominance, in which an individual asserts control over others or benefits most after social conflict, has an influence on social behaviour. However, the mechanisms mediating social dominance remain unclear. Social dominance within social groups determines the distribution of rewards such as food and access to mating partners, which can act as reinforcers. In this study, we used the water competition test to determine whether mice were dominant or subordinate. It has been previously reported that mice heterozygous for a missense mutation in Grin1 (Grin1 ) showed altered social behaviour, with increased locomotor activity, novelty seeking and anxiety. However, social dominance in these mice has not been previously investigated. We subjected Grin1 mice to the water competition test using IntelliCage and observed that Grin1 influences competitive dominance. We found that Grin1 mice exhibited social subordination characterised by decreased corner visit frequency and occupancy time at the beginning of the task. However, Grin1 mice retained increased basal activity and exploring behaviour under a group-housed environment. Our findings suggested that Grin1 plays an important role in determining social dominance.
社会支配地位，即个体在社会冲突后主张对他人的控制或获得最大利益，会对社会行为产生影响。然而，介导社会支配地位的机制仍不清楚。社会群体内部的支配地位决定了奖励的分配，如食物和交配伴侣的获取，这些奖励可以作为强化物。在这项研究中，我们使用了水竞争测试来确定老鼠是支配型还是从属型。先前有报道称，Grin1 错义突变杂合的小鼠表现出改变的社会行为，表现为运动活性增加、寻求新奇和焦虑。然而，这些小鼠的社会支配地位尚未被研究过。我们使用 IntelliCage 对 Grin1 小鼠进行了水竞争测试，发现 Grin1 影响竞争优势。我们发现 Grin1 小鼠表现出社会从属的特征，表现在任务开始时角落访问频率和占据时间减少。然而，Grin1 小鼠在群体饲养环境下保持着增加的基础活动和探索行为。我们的研究结果表明，Grin1 在决定社会支配地位方面起着重要作用。
