School of Life Sciences, Arizona State University, 427 East Tyler Mall, Tempe, AZ 85281, USA; Centre d'Etudies Biologiques de Chizé, CNRS, 79360 Villiers en Bois, France.
School of Life Sciences, Arizona State University, 427 East Tyler Mall, Tempe, AZ 85281, USA.
Gen Comp Endocrinol. 2020 Mar 1;288:113375. doi: 10.1016/j.ygcen.2019.113375. Epub 2019 Dec 24.
Plasma corticosterone (CORT) concentrations fluctuate in response to homeostatic demands. CORT is widely recognized as an important hormone related to energy balance. However, far less attention has been given to the potential role of CORT in regulating salt and water balance or responding to osmotic imbalances. We examined the effects of reproductive and hydric states on CORT levels in breeding Children's pythons (Antaresia childreni), a species with substantial energetic and hydric costs associated with egg development. Using a 2 × 2 experimental design, we examined how reproduction and water deprivation, both separately and combined, impact CORT levels and how these changes correlate with hydration (plasma osmolality) and energy levels (blood glucose). We found that reproduction leads to increased CORT levels, as does dehydration induced by water deprivation. The combined impact of reproduction and water deprivation led to the largest increases in CORT levels. Additionally, we found significant positive relationships among CORT levels, plasma osmolality, and blood glucose. Our results provide evidence that both reproductive activity and increased plasma osmolality can lead to increased plasma CORT in an ectotherm, which could be explained by either CORT having a role as a mineralocorticoid or CORT being elevated as part of a stress response to resource imbalances.
血浆皮质酮（CORT）浓度会随生理需求波动。CORT 被广泛认为是与能量平衡有关的重要激素。然而，人们对 CORT 在调节盐和水平衡或应对渗透失衡方面的潜在作用关注甚少。我们研究了繁殖和水分状态对繁殖儿童蟒蛇（Antaresia childreni）的 CORT 水平的影响，该物种的卵发育需要大量的能量和水分。我们使用 2×2 实验设计，研究了繁殖和水分剥夺分别以及共同作用如何影响 CORT 水平，以及这些变化如何与水合作用（血浆渗透压）和能量水平（血糖）相关。我们发现繁殖会导致 CORT 水平升高，水分剥夺引起的脱水也是如此。繁殖和水分剥夺的综合影响导致 CORT 水平的最大升高。此外，我们发现 CORT 水平、血浆渗透压和血糖之间存在显著的正相关关系。我们的结果提供了证据表明，繁殖活动和血浆渗透压升高都可能导致变温动物的血浆 CORT 升高，这可以用 CORT 作为盐皮质激素的作用来解释，也可以用 CORT 作为对资源失衡的应激反应的一部分来解释。
