Roles of stress hormones in food intake regulation in anuran amphibians throughout the life cycle
Roles of stress hormones in food intake regulation in anuran amphibians throughout the life cycle
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DOI：
10.1016/j.cbpb.2004.12.007
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发表时间：
2005-08-01
影响因子：
2.3
通讯作者：
Denver, RJ
中科院分区：
文献类型：
--
作者：
Crespi, EJ;Denver, RJ
为了了解脊椎动物能量平衡调节的个体发生学，我们分析了西方斑腿蟾蜍(Spea Hammondii)在变态前、变态前和幼体三个发育阶段促肾上腺皮质激素释放因子(CRF)和皮质酮对食物缺乏的反应。皮质酮对5天食物剥夺的反应因发育阶段不同而异。随着食物的缺乏，变态前和变态前的蝌蚪都会增加全身皮质酮的含量，但变态前的蝌蚪对皮质酮的反应幅度明显更大。相比之下，幼蛙降低了血浆皮质酮浓度，类似地，大脑CRF肽含量在缺乏食物的蝌蚪中有增加的趋势，但在缺乏食物的青少年中没有变化。因此，在两栖动物中，下丘脑-垂体-肾间轴(HPI)对食物匮乏的反应方式存在个体发育差异。在蝌蚪中，HPI轴在禁食后被激活，就像在鸟类和哺乳动物中看到的那样，这可能与动员储存的燃料和增加觅食有关。幼蛙对食物缺乏的反应不是通过激活HPI轴，而是追求一种包括降低血浆皮质酮浓度的能量节约策略。(C)2005 Elsevier Inc.保留所有权利。
Towards understanding the ontogeny of energy balance regulation in vertebrates we analyzed the responses of corticotropin-releasing factor (CRF) and corticosterone to food deprivation in the Western spadefoot toad (Spea hammondii) at three developmental stages: premetamorphic tadpole, prometamorphic tadpole, and juvenile. Corticosterone responses to 5 days of food deprivation varied among developmental stages. Both pre- and prometamorphic tadpoles increased whole-body corticosterone content with food deprivation, but the magnitude of the response of premetamorphic tadpoles was significantly greater. By contrast, juvenile toads decreased plasma corticosterone concentration, Similarly, brain CRF peptide content tended to increase in food-deprived tadpoles but did not change in food-deprived juveniles. Therefore, there is an ontogenetic difference in the way the hypothalamic-pituitary-inteffenal (HPI) axis responds to food deprivation in amphibians. In tadpoles, the HPI axis is activated in response to fasting as is seen in birds and mammals, and may be associated with mobilization of stored fuels and increased foraging. Juvenile toads do not respond to food deprivation by activating the HPI axis, but instead pursue a strategy of energy conservation that involves a reduction in plasma corticosterone concentration. (c) 2005 Elsevier Inc. All rights reserved.