Comparing techniques for measuring corticosterone in tadpoles  

作　　者：Pablo BURRACO Rosa ARRIBAS Saurabh S. KULKARNI Daniel R. BUCHHOLZ Ivan GOMEZ-MESTRE 

机构地区：[1]Department of Wetland Ecology, Estacion Biologica de Dofiana (EBD-CSIC), C/Americo Vespucio, s/n, 41092 Sevilla, Spain [2]Department of Pediatrics, Yale School of Medicine, Yale University, New Haven, CT 0651, USA [3]Department of Biological Sciences, University of Cincinnati, Cincinnati, OH 45221, USA

出　　处：《Current Zoology》2015年第5期835-845,共11页动物学报（英文版）

摘　　要：Glucocorticoids play a key role in mediating stress responses in vertebrates. Corticosterone （CORT） is the main glucocorticoid produced in amphibians, birds, and reptiles, and regulates several metabolic functions. The most common methods for quantifying CORT are competitive binding immunoassays： radioimmunoassay （RIA） and enzyme immunoassay （EIA）. RIA has been broadly used since the 1980＇s but it requires radioactivity. Commercial EIA kits permit quantifying hormone levels without radioactivity although the requirement for a larger sample volume may be a strong limitation for measurements involving larval amphibians. Here we used Xenopus laevis tadpoles to compare the performance of three commonly used procedures for determination of CORT： RIA on a chloroform extract of whole-body homogenate, EIA on plasma, and EIA on supematant of whole-body homogenate. We treated tadpoles with exogenous CORT at 0, 25, 50, and 100 nM. RIA could distinguish between 0 and 25 nM, and EIA on plasma between 0 and 50 nM, whereas whole-body homogenate EIA only detected significant differences between 0 and 100 riM. Each procedure presents advantages and disadvantages regarding sensitivity, the use of radioactivity, sample size, handling time, and economic cost. RIA is preferred when studying small-bodied animals from which blood samples cannot be obtained. When CORT level differences are intermediate and blood sampling is possible, EIA on plasma is a good non-radioactive alternative. EIA on whole-body homogenates may be useful to assess qualitative changes in CORT levels when considerable differences are expected. Finally, we discuss our findings in the context of previous studies on CORT in amphibians [Current Zoology 61 （5）： 835-845, 2015].

关 键 词：CORTICOSTERONE RADIOIMMUNOASSAY Enzyme immunoassay GLUCOCORTICOIDS AMPHIBIANS STRESS 

分 类 号：Q577[生物学—生物化学] S966.31[农业科学—水产养殖]