1 Division of Behavioural Ecology, Institute of Ecology and Evolution, University of Bern , Wohlenstrasse 50A, 3032 Hinterkappelen , Switzerland.
2 Neuchâtel Platform of Analytical Chemistry, Institute of Chemistry, University of Neuchâtel , Avenue de Bellevaux 51, 2009 Neuchâtel , Switzerland.
Philos Trans R Soc Lond B Biol Sci. 2019 Apr 15;374(1770):20180119. doi: 10.1098/rstb.2018.0119.
In many vertebrate species, early social experience generates long-term effects on later life social behaviour. These effects are accompanied by persistent modifications in the expression of genes implicated in the stress axis. It is unknown, however, whether stress axis programming can affect the development of social competence, and if so, by which mechanism(s). Here, we used pharmacological manipulations to persistently reprogramme the hypothalamic-pituitary-interrenal axis of juvenile cooperatively breeding cichlids, Neolamprologus pulcher. During the first two months of life, juveniles were repeatedly treated with cortisol, mifepristone or control treatments. Three months after the last manipulation, we tested for treatment effects on (i) social competence, (ii) the expression of genes coding for corticotropin-releasing factor ( crf), glucocorticoid receptor ( gr1) and mineralocorticoid receptor ( mr) in the telencephalon and hypothalamus and (iii) cortisol levels. Social competence in a social challenge was reduced in cortisol-treated juveniles, which is in accordance with previous work applying early-life manipulations using different social experiences. During early life, both cortisol and mifepristone treatments induced a persistent downregulation of crf and upregulation of mr in the telencephalon. We suggest that these persistent changes in stress gene expression may represent an effective physiological mechanism for coping with stress. This article is part of the theme issue 'Developing differences: early-life effects and evolutionary medicine'.
在许多脊椎动物物种中，早期的社会经验会对后期的社会行为产生长期影响。这些影响伴随着与应激轴相关的基因表达的持久改变。然而，目前尚不清楚应激轴编程是否会影响社交能力的发展，如果是，其机制是什么。在这里，我们使用药理学方法对幼年合作繁殖的慈鲷 Neolamprologus pulcher 的下丘脑-垂体-肾上腺轴进行了持续的重编程。在生命的头两个月，幼鱼反复接受皮质醇、米非司酮或对照处理。最后一次处理三个月后，我们测试了处理对（i）社交能力、（ii）脑和下丘脑内编码促肾上腺皮质释放因子 (crf)、糖皮质激素受体 (gr1) 和盐皮质激素受体 (mr) 的基因表达以及（iii）皮质醇水平的影响。在社交挑战中，皮质醇处理的幼鱼的社交能力降低，这与之前使用不同社交经验进行早期生活处理的工作一致。在生命早期，皮质醇和米非司酮处理都诱导了脑内 crf 的持续下调和 mr 的上调。我们认为，这些应激基因表达的持久变化可能代表了一种应对压力的有效生理机制。本文是主题为“发展差异：早期影响和进化医学”的特刊的一部分。
