Fighting experience alters brain androgen receptor expression dependent on testosterone status

Contest decisions are influenced by the outcomes of recent fights (winner–loser effects). Steroid hormones and serotonin are closely associated with aggression and therefore probably also play important roles in mediating winner–loser effects. In mangrove rivulus fish, Kryptolebias marmoratus, individuals with higher testosterone (T), 11-ketotestosterone and cortisol levels are more capable of winning, but titres of these hormones do not directly mediate winner–loser effects. In this study, we investigated the effects of winning/losing experiences on brain expression levels of the receptor genes for androgen (AR), oestrogen α/β (ERα/β), glucocorticoid (GR) and serotonin (5-HT1AR). The effect of contest experience on AR gene expression depended on T levels: repeated losses decreased, whereas repeated wins increased AR gene expression in individuals with low T but not in individuals with medium or high T levels. These results lend strong support for AR being involved in mediating winner–l...争斗决策受近期打斗结果的影响，即胜负效应（winner-loser effects）。类固醇激素与血清素（serotonin）和攻击行为密切相关，因此可能在介导胜负效应中发挥重要作用。在斑隐棘鳉（Kryptolebias marmoratus，俗称红树林溪鳉）中，睾酮（testosterone，T）、11-酮睾酮及皮质醇（cortisol）水平更高的个体获胜能力更强，但这些激素的滴度并未直接介导胜负效应。本研究探究了胜负经历对斑隐棘鳉脑内雄激素受体（androgen receptor，AR）、雌激素受体α/β（oestrogen receptor α/β，ERα/β）、糖皮质激素受体（glucocorticoid receptor，GR）及血清素1A受体（serotonin 1A receptor，5-HT1AR）的基因表达水平的影响。争斗经历对AR基因表达的影响取决于睾酮水平：在睾酮水平较低的个体中，重复失败会降低AR基因表达，而重复获胜则会升高其表达，但该效应在睾酮水平中等或较高的个体中并未出现。上述结果为AR参与介导胜负效应提供了强有力的支持。