Corticosterone inhibits feather growth: Potential mechanism explaining seasonal down regulation of corticosterone during molt
Corticosterone inhibits feather growth: Potential mechanism explaining seasonal down regulation of corticosterone during molt
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DOI：
10.1016/j.cbpa.2005.07.014
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发表时间：
2005-09-01
影响因子：
2.3
通讯作者：
Wingfield, JC
中科院分区：
文献类型：
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作者：
Romero, LM;Strochlic, D;Wingfield, JC
在许多雀形目动物中，皮质酮 (CORT) 会受到季节性调节，在所有羽毛都被更换的前基础蜕皮期间，血浆 CORT 浓度最低。为了解释原因，我们提出鸟类在蜕皮过程中下调天然 CORT 释放，以避免 CORT 对蛋白质的降解作用及其对蛋白质合成的抑制。如果 CORT 在蜕皮期间发挥这些作用，它可能会减缓羽毛生产过程中的蛋白质沉积，并可能导致较长时期的飞行性能下降。为了检验这一假设，将空的或填充有 CORT 的硅橡胶植入物插入圈养的欧洲椋鸟 (Sturnus vulgaris) 和白冠麻雀 (Zonotrichia leucophrys) 体内，进行诱导（拔毛后更换羽毛）和自然蜕皮。然后，我们通过定期测量初级羽毛、次级羽毛和尾羽的长度来测量羽毛重新生长的速度。与对照动物相比，植入 CORT 的鸟类羽毛生长速度显着降低。还比较了诱导换羽和非换羽鸟类的基础 CORT 浓度，但没有发现差异。结果表明，对于鸟类的生存来说，一整套新羽毛可能比 CORT 对压力源做出最大反应的能力更重要。 (c) 2005 Elsevier Inc. 保留所有权利。
Corticosterone (CORT) is seasonally modulated in many passerines, with plasma CORT concentrations lowest during the prebasic molt when all feathers are replaced. To explain why, we proposed that the birds downregulate natural CORT release during molt in order to avoid CORT's degradative effects on proteins and its inhibition of protein synthesis. If CORT exerted these effects during molt, it could slow protein deposition during feather production and potentially result in a longer period of degraded flight performance. To test this hypothesis, either empty or CORT-filled silastic implants were inserted into captive European starlings (Sturnus vulgaris) and white-crowned sparrows (Zonotrichia leucophrys) undergoing induced (feather replacement after plucking) and natural molts. We then measured the rate of feather re-growth by regularly measuring the length of primary, secondary, and tail feathers. CORT implanted birds showed a significantly decreased rate of feather growth compared to control animals. Basal CORT concentrations of induced molt and non-molting birds were also compared but no difference was noted. The results suggest a tradeoff, a complete set of new feathers may be more important to the survival of a bird than the ability of CORT to respond maximally to a stressor. (c) 2005 Elsevier Inc. All rights reserved.