Endocrine regulation of fueling by hyperphagia in migratory birds
Endocrine regulation of fueling by hyperphagia in migratory birds
复制标题
DOI：
10.1007/s00359-017-1152-1
复制
发表时间：
2017-07-01
影响因子：
2.1
通讯作者：
Eikenaar, Cas
中科院分区：
文献类型：
--
作者：
Eikenaar, Cas
为了支持迁徙的耐力飞行，鸟类通过进食过多（补充燃料）来积累大量脂肪。尽管影响移民加油动机的因素已得到很好的描述，但调节加油的生理机制却很大程度上未知。激素可能参与其中，并且可以说，在食物摄入和补充能量方面研究最好的是皮质酮。皮质酮具有许可效应，因为阻断激素的作用会阻碍有效的能量补充。尽管没有迹象表明皮质酮会刺激补充能量，一些研究甚至观察到皮质酮水平与食物摄入量和补充速度之间呈负相关。后者是出乎意料的，因为缓慢的加油可能会降低整体的迁移速度。为了检验这些负相关性的因果关系，我以非侵入性方式增加了圈养候鸟的循环皮质酮水平，并确定了其对食物摄入和燃料积累的影响。皮质酮治疗组和对照治疗组之间的食物摄入量和燃料积累均没有差异。这表明皮质酮不会妨碍中途停留期间的食物摄入和补充能量，也不会刺激这些过程。调节迁移性食欲亢进的有希望的替代候选者是由脂肪组织、肠道或胃肠道分泌的“食欲调节”激素。下一代测序的进步将有助于在研究这些问题时采用自下而上的方法。
To support migratory endurance flight, birds accumulate large amounts of fat by hyperphagia (fueling). Whereas the factors influencing migrants' motivation to fuel are well described, the physiological mechanism regulating fueling is largely unknown. Hormones are likely involved and arguably the best studied with respect to food intake and fueling is corticosterone. Corticosterone has a permissive effect, as blocking the hormone's actions prohibits efficient fueling. There are no indications, though that corticosterone stimulates fueling, and some studies even observed negative correlations between corticosterone level and food intake and speed of fueling. The latter is unexpected as slow fueling could reduce the overall speed of migration. To test the causality of these negative correlations, I non-invasively increased circulating corticosterone levels in captive migrants and determined its effect on food intake and fuel accumulation. Neither food intake nor fuel accumulation differed between corticosterone-treated and control-treated individuals. This indicates that corticosterone does not hamper food intake and fueling during stopovers, nor does it stimulate these processes. Promising alternative candidates for the regulation of migratory hyperphagia are 'appetite regulating' hormones secreted by the adipose tissue, gut, or gastro-intestinal tract. The advance of next-generation sequencing will facilitate a bottom-up approach when investigating these.