Saltzman Wendy, Hogan Brynn K, Allen Amy J, Horman Brian M, Abbott David H
Department of Biology, University of California, Riverside, CA 92521, USA.
Psychoneuroendocrinology. 2006 Jul;31(6):692-702. doi: 10.1016/j.psyneuen.2006.01.006. Epub 2006 Apr 18.
Behaviorally subordinate female marmosets undergo social suppression of ovulation and hypoestrogenism, as well as chronic reductions in circulating basal cortisol concentrations. Because estrogen elevates hypothalamic-pituitary-adrenal axis activity and circulating glucocorticoid levels in other species, we tested the hypothesis that socially induced hypoestrogenism contributes to cortisol reductions in subordinate female marmosets. We characterized morning basal plasma cortisol levels, as well as cortisol responses to exogenous adrenocorticotropic hormone (ACTH; 0, 1, or 10 microg/kg), in seven anovulatory subordinate females and six ovariectomized, non-subordinate females under two conditions: during long-term treatment with estradiol (E2) and control. Circulating E2 and cortisol levels were compared to those of six dominant females undergoing ovulatory cycles. Basal cortisol concentrations in the control condition were significantly lower in subordinates than in both dominant and ovariectomized females. E2 treatment elevated circulating E2 levels of subordinate and ovariectomized females into the range seen in dominant females but did not increase either mean basal or ACTH-stimulated cortisol levels. To the contrary, E2 treatment caused a decline in basal cortisol levels over time, especially in ovariectomized animals. These results indicate that treatment with exogenous estrogen does not elevate circulating cortisol levels in previously hypoestrogenemic female marmosets and, correspondingly that socially induced hypoestrogenism does not diminish cortisol levels in subordinate females.
行为上处于从属地位的雌性狨猴会经历排卵的社会抑制和雌激素水平过低，以及循环基础皮质醇浓度的慢性降低。由于雌激素会提高其他物种下丘脑-垂体-肾上腺轴的活性和循环糖皮质激素水平，我们测试了这样一个假设，即社会诱导的雌激素水平过低会导致从属雌性狨猴的皮质醇降低。我们对7只无排卵的从属雌性和6只卵巢切除的非从属雌性在两种情况下的早晨基础血浆皮质醇水平以及对外源性促肾上腺皮质激素（ACTH；0、1或10微克/千克）的皮质醇反应进行了表征：在长期接受雌二醇（E2）治疗期间和对照期间。将循环E2和皮质醇水平与6只处于排卵周期的优势雌性的水平进行了比较。在对照条件下，从属雌性的基础皮质醇浓度显著低于优势雌性和卵巢切除的雌性。E2治疗将从属雌性和卵巢切除雌性的循环E2水平提高到优势雌性所见的范围内，但并未增加平均基础或ACTH刺激的皮质醇水平。相反，E2治疗导致基础皮质醇水平随时间下降，尤其是在卵巢切除的动物中。这些结果表明，用外源性雌激素治疗不会提高先前雌激素水平过低的雌性狨猴的循环皮质醇水平，相应地，社会诱导的雌激素水平过低也不会降低从属雌性的皮质醇水平。
