Modifications of a field method for fecal steroid analysis in baboons
Modifications of a field method for fecal steroid analysis in baboons
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DOI：
10.1016/j.physbeh.2004.03.012
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发表时间：
2004-09-15
影响因子：
2.9
通讯作者：
Whitten, PL
中科院分区：
文献类型：
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作者：
Beehner, JC;Whitten, PL
通过从粪便中提取类固醇代谢物，研究人员可以无创地跟踪自由放养动物的内分泌活动。样品保存是这种方法的关键组成部分，因为类固醇代谢物迅速分解。在这里，我们描述了一种方法，用于保存，现场提取和放射免疫分析的类固醇代谢产物（雌二醇，孕酮，糖皮质激素和睾酮）从野生雌性狒狒（狒狒属）的粪便。该方法是Stavisky [社会内分泌学：用于监测圈养和自由放养灵长类动物生殖功能的非侵入性技术]开发的方法的修改。埃默里大学博士，1994年]，其采用反相十八烷基硅烷柱从粪便中提取类固醇。除了为该方法提供生理学验证外，我们还检查了不同（1）采集时间（上午与下午）、（2）甲醇提取处理（均质化与手动混合）和（3）固相提取时间（采集后2小时与10小时）的类固醇浓度变化。然后，我们检查样品储存在环境温度和零度以下的温度下的稳定性，以确定是否存储时间显着改变类固醇浓度。我们的研究结果表明，激素浓度没有不同的上午和下午的样品，均质化产生显着更高的粪便类固醇浓度，和粪便类固醇是稳定的甲醇/丙酮溶液长达10小时。当在环境温度下储存时，只有糖皮质激素代谢物在长达40天的时间内发生一定程度的降解。然而，当在-10 ℃下储存时，长达400天没有观察到显著的类固醇变化。这种方法特别适合于行为研究，因为它允许样品收集和样品处理之间的延迟，从而允许行为观察继续进行。(C)2004年爱思唯尔公司All rights reserved.
By extracting steroid metabolites from feces, researchers can track endocrine activity noninvasively in free-ranging animals. Sample preservation is a critical component of such methods because steroid metabolites rapidly decompose. Here, we describe a method for preservation, field extraction, and radioimmunoassay of steroid metabolites (estradiol, progesterone, glucocorticoids, and testosterone) from the feces of wild female baboons (Papio spp.). This method is a modification of that developed by Stavisky [Socioendocrinology: noninvasive techniques for monitoring reproductive function in captive and free-ranging primates. PhD, Emory University, 1994.], which employs reversed-phase octadecylsilane cartridges to extract steroids from feces. In addition to providing physiological validation for this method, we examine variation in steroid concentration across different (1) collection times (morning vs. afternoon), (2) methanol extraction treatments (homogenized vs. hand-mixed), and (3) solid-phase extraction times (2 vs. 10 h after collection). We then examine the stability of sample storage at ambient and subzero temperatures to determine whether storage time significantly alters steroid concentrations. Our results show that hormone concentrations do not differ between morning and afternoon samples, homogenization yields significantly higher fecal steroid concentrations, and fecal steroids are stable in a methanol/acetone solution for up to 10 h. When stored at ambient temperatures, only glucocorticoid metabolites had some degradation over a period of up to 40 days. However, when stored at -10degreesC, no significant steroid changes were observed for up to 400 days. This method is particularly suited for behavioral research because it permits delays between sample collection and sample processing, thus allowing behavioral observations to continue. (C) 2004 Elsevier Inc. All rights reserved.