Seasonal changes in glucocorticoid and testosterone concentrations in free-living arctic ground squirrels from the boreal forest of the Yukon
Seasonal changes in glucocorticoid and testosterone concentrations in free-living arctic ground squirrels from the boreal forest of the Yukon
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DOI：
10.1139/cjz-79-1-49
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发表时间：
2001-01-01
影响因子：
1.4
通讯作者：
McColl, CJ
中科院分区：
文献类型：
--
作者：
Boonstra, R;Hubbs, AH;McColl, CJ
我们研究了糖皮质激素和睾酮浓度从春季到夏季的变化livetraping自由生活的北极地松鼠（Spermophilus parryii）的人口。主要的糖皮质激素是皮质醇，大多数人的皮质酮浓度低于可测量的浓度。Livetraping引起了强烈的压力反应，在两种性别：繁殖男性和女性被困在春天的自由皮质醇浓度分别为4和34倍，基线动物。最大的皮质类固醇结合能力（MCBC）是不受诱捕，约3倍以上的繁殖女性比繁殖男性。在活跃的季节，MCBC值最低的所有男性类（青少年，nonreproductive成年人，和生殖成年人），是不到一半的所有女性类，怀孕女性的值约两倍的少女。然而，游离皮质醇浓度在所有女性类和少年男性和成年男性的一半左右。与基线雄性样本中发现的睾酮浓度相比，活体诱捕增加了雄性的睾酮浓度，并且睾酮浓度不影响MCBC值。在livetraped动物中的睾酮浓度显着不同的男性类，与非生殖男性保持浓度的64%，在繁殖男性和10倍，在青少年。
We examined how glucocorticoid and testosterone concentrations changed from spring to summer by livetrapping free-living populations of arctic ground squirrels (Spermophilus parryii). The primary glucocorticoid was found to be cortisol, with corticosterone below measurable concentrations in most individuals. Livetrapping elicited a strong stress response in both sexes: breeding males and females trapped in spring had free cortisol concentrations 4 and 34 times, respectively, those of base-line animals. The maximum corticosteroid-binding capacity (MCBC) was unaffected by trapping and was about 3 times higher in breeding females than in breeding males. Over the active season, MCBC values were lowest in all male classes (juveniles, nonreproductive adults, and reproductive adults), being less than half those in all female classes; pregnant females had values approximately twice those of juvenile females. However, free cortisol concentrations were similar in all female classes and in juvenile males and about half those in adult males. Livetrapping increased testosterone concentrations in males over those found in samples from base-line males, and testosterone concentrations did not affect MCBC values. Testosterone concentrations in livetrapped animals differed significantly among male classes, with nonreproductive males maintaining concentrations 64% of those in breeding males and 10 times those in juveniles.