Ruthsatz Katharina, Dausmann Kathrin H, Paesler Katharina, Babos Patricia, Sabatino Nikita M, Peck Myron A, Glos Julian
Institute of Zoology, Universität Hamburg, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany.
Zoological Institute, Technische Universität Braunschweig, Mendelssohnstraße 4, 38106 Braunschweig, Germany.
Conserv Physiol. 2020 Dec 14;8(1):coaa100. doi: 10.1093/conphys/coaa100. eCollection 2020.
Effective conservation actions require knowledge on the sensitivity of species to pollution and other anthropogenic stressors. Many of these stressors are endocrine disruptors (EDs) that can impair the hypothalamus-pituitary-thyroid axis and thus alter thyroid hormone (TH) levels with physiological consequences to wildlife. Due to their specific habitat requirements, amphibians are often sentinels of environmental degradation. We investigated how altered TH levels affected the bioenergetics of growth and development (i.e. age, size, metabolism, cardiac function and energy stores) before, during and after metamorphosis in the European common frog ( We also determined how ontogenetic stage affected susceptibility to endocrine disruption and estimated juvenile performance. TH levels significantly affected growth and energetics at all developmental stages. Tadpoles and froglets exposed to high TH levels were significantly younger, smaller and lighter at all stages compared to those in control and low TH groups, indicating increased developmental and reduced growth rates. Across all ontogenetic stages tested, physiological consequences were rapidly observed after exposure to EDs. High TH increased heart rate by an average of 86% and reduced energy stores (fat content) by 33% compared to controls. Effects of exposure were smallest after the completion of metamorphosis. Our results demonstrate that both morphological and physiological traits of the European common frog are strongly impacted by endocrine disruption and that ontogenetic stage modulates the sensitivity of this species to endocrine disruption. Since endocrine disruption during metamorphosis can impair the physiological stress response in later life stages, long-term studies examining carry-over effects will be an important contribution to the conservation physiology of amphibians.
有效的保护行动需要了解物种对污染和其他人为压力源的敏感性。其中许多压力源是内分泌干扰物（EDs），它们会损害下丘脑 - 垂体 - 甲状腺轴，从而改变甲状腺激素（TH）水平，给野生动物带来生理影响。由于两栖动物对特定栖息地有要求，它们常常是环境退化的指示物种。我们研究了在欧洲普通青蛙变态发育之前、期间和之后，甲状腺激素水平的改变如何影响生长和发育的生物能量学（即年龄、大小、新陈代谢、心脏功能和能量储备）。我们还确定了个体发育阶段如何影响对内分泌干扰的易感性，并评估了幼体的表现。甲状腺激素水平在所有发育阶段都对生长和能量学有显著影响。与对照组和低甲状腺激素组相比，暴露于高甲状腺激素水平的蝌蚪和幼蛙在各个阶段都明显更年幼、更小且更轻，这表明发育速度加快而生长速度减慢。在所有测试的个体发育阶段中，暴露于内分泌干扰物后很快就观察到了生理影响。与对照组相比，高甲状腺激素使心率平均增加了86%，并使能量储备（脂肪含量）减少了33%。变态发育完成后，暴露的影响最小。我们的结果表明，欧洲普通青蛙的形态和生理特征都受到内分泌干扰的强烈影响，并且个体发育阶段调节了该物种对内分泌干扰的敏感性。由于变态发育期间的内分泌干扰会损害后期生命阶段的生理应激反应，研究遗留效应的长期研究将对两栖动物的保护生理学做出重要贡献。
