6天的饥饿使斑马鱼在社会冲突中获胜
饥饿会增强从缰核(habenula）到IPN的获胜途径
饥饿诱导的食欲素信号偏倚在IPN中AMPAR基因的剪接
AMPAR剪接变体的活性被延长，从而驱动IPN中的突触增强
许多动物都会同种物种之间争夺统治权。因为获胜者比失败者可以获得更多的资源，所以战斗结果对于动物的生存至关重要，尤其是在饥饿等资源不足的情况下。但是，目前尚不清楚饥饿是否以及如何影响战斗结果。本研究中，日本RIKEN脑科学中心的Haruna Nakajo、Ming-Yi Chou和Hitoshi Okamoto*等人调查了食物匮乏对斑马鱼的大脑活动和战斗行为的影响。研究表明饥饿有助于在社会冲突中获胜。在战斗之前，饥饿的鱼显示出对背侧缰核（dorsal habenula，dHbL）-背/中间足突间核通路（dorsal/intermediate interpeduncular nucleus，d/iIPN）的外侧亚区的增强作用，这被认为是在打赢后必不可少的。由下丘脑的食欲素/促胰泌素神经肽介导的回路增强，通过增加AMPAR亚基的翻转型可替代剪接变体的表达来延长AMPA型谷氨酸受体(AMPAR)的活性。这种机制可能是饥饿的脊椎动物赢得战斗的基础，并且可能在动物系统发育中普遍存在。
Abstract
Hunger Potentiates the Habenular Winner Pathway for Social Conflict by Orexin-Promoted Biased Alternative Splicing of the AMPA Receptor Gene
Haruna Nakajo，Ming-Yi Chou，Ming-Yi Chou，Masae Kinoshita，Hideaki Shimazaki，Takashi Tsuboi，Hitoshi Okamoto
Many animals fight for dominance between conspecifics. Because winners could obtain more resources than losers, fighting outcomes are important for the animal’s survival, especially in a situation with insufficient resources, such as hunger. However, it remains unclear whether and how hunger affects fighting outcomes. Herein, we investigate the effects of food deprivation on brain activity and fighting behaviors in zebrafish. We report that starvation induces winning in social conflicts. Before the fights, starved fish show potentiation of the lateral subregion of the dorsal habenula (dHbL)-dorsal/intermediate interpeduncular nucleus (d/iIPN) pathway, which is known to be essential for and potentiated after winning fights. Circuit potentiation is mediated by hypothalamic orexin/hypocretin neuropeptides, which prolong AMPA-type glutamate receptor (AMPAR) activity by increasing the expression of a flip type of alternative splicing variant of the AMPAR subunit. This mechanism may underlie how hungry vertebrates win fights and may be commonly shared across animal phylogeny.
