Laboratoire Ecologie et Evolution, UMR 7625 Université Pierre et Marie Curie, 7, quai Saint-Bernard, 75005 Paris, France.
J Exp Biol. 2010 Jun 15;213(Pt 12):2116-24. doi: 10.1242/jeb.040220.
Environmental factors including stressors, health status and social context significantly affect carotenoid-based coloration. For instance, stressors may induce the diversion of carotenoids from pigmentation pathways, potentially explaining why stressed animals often exhibit reduced coloration. However, we recently showed that high blood corticosterone concentrations, which are part of the physiological stress response, are associated with increased redness of the belly in the common lizard (Lacerta vivipara). This result clearly contrasts with the findings of many studies of carotenoid-based coloration because corticosterone is believed to increase oxidative stress. Here, we examined whether these positive effects are influenced by differences in food availability. We tested the effect of high corticosterone levels on carotenoid-based coloration, antioxidant enzyme activity and oxidative damage in common lizards subject to low and high food availability. Food restriction abolished the carotenoid-based color enhancement when corticosterone concentrations in animals were high. We discuss how carotenoid-based color can honestly signal individual quality in this species and how the increased redness induced by corticosterone could be a terminal investment in an environment where long-term survival prospects are poor but not when immediate survival is endangered.
环境因素，包括应激源、健康状况和社会环境，会显著影响类胡萝卜素着色。例如，应激源可能会使类胡萝卜素从色素形成途径转移，这可能解释了为什么处于压力下的动物通常表现出颜色变浅。然而，我们最近发现，血液中皮质酮浓度（生理应激反应的一部分）与常见蜥蜴（蜥蜴属 vivipara）腹部变红有关。这一结果与许多基于类胡萝卜素的颜色研究的发现明显相反，因为皮质酮被认为会增加氧化应激。在这里，我们研究了这些积极影响是否受到食物供应差异的影响。我们测试了高皮质酮水平对低和高食物供应条件下常见蜥蜴的基于类胡萝卜素的颜色、抗氧化酶活性和氧化损伤的影响。当动物体内皮质酮浓度较高时，食物限制会消除基于类胡萝卜素的颜色增强。我们讨论了在这种物种中，基于类胡萝卜素的颜色如何诚实地反映个体质量，以及皮质酮诱导的红色增加如何成为在长期生存前景较差但当前生存不受威胁的环境中的一种终级投资。
