Department of Life Science, Faculty of Science and Technology, Kindai University, Higashiosaka, Osaka 577-8502, Japan.
Department of Life Science, Faculty of Science and Technology, Kindai University, Higashiosaka, Osaka 577-8502, Japan,
Zoolog Sci. 2020 Oct;37(5):391-398. doi: 10.2108/zs200045.
In this study, we used the immediate early gene, egr-1, as a marker for neural activation and examined whether egr-1 expression is affected in brain regions associated with the social behavioral network (SBN) when social rank is determined and changed in male medaka fish (). Based on the behavioral contest protocol used in this study, we obtained four types of males: social ascending, social descending, dominant, and subordinate. In some brain regions associated with the SBN, we detected higher egr-1 expression in ascending and descending males than in dominant and subordinate males. Social-rank stable males (i.e., dominant and subordinate male fish) showed a similar level of egr-1 expression as the control male fish, which were housed without social stimulus of encountering another conspecific. These findings suggested that the transitioning of social rank could enhance neural activity in some brain regions associated with the SBN in male medaka. The use of medaka fish has many advantages in various fields of research such as genetics, developmental biology, environmental biology, and behavioral neurology. The findings of this study would contribute to future research exploring the roles of the SBN regions in regulating physiological and behavioral events associated with social-rank transition.
在这项研究中，我们使用即时早期基因 egr-1 作为神经激活的标志物，研究当雄性青鳉鱼的社会等级确定和改变时，其与社会行为网络（SBN）相关的大脑区域中的 egr-1 表达是否受到影响。基于本研究中使用的行为竞争方案，我们获得了四种类型的雄性个体：社会上升型、社会下降型、优势型和劣势型。在与 SBN 相关的一些大脑区域中，我们检测到上升型和下降型雄性个体的 egr-1 表达高于优势型和劣势型雄性个体。社会等级稳定的雄性个体（即优势型和劣势型雄性鱼类）与没有遇到同种个体的社会刺激的对照雄性鱼类表现出相似水平的 egr-1 表达。这些发现表明，社会等级的转变可以增强与 SBN 相关的一些大脑区域的神经活动。青鳉鱼在遗传、发育生物学、环境生物学和行为神经学等各个研究领域都有许多优势。本研究的发现将有助于未来研究探索 SBN 区域在调节与社会等级转变相关的生理和行为事件中的作用。
