Brasfield Sandra M, Talent Larry G, Janz David M
Department of Zoology, Oklahoma State University, Stillwater, Oklahoma.
Zoo Biol. 2008 Jan;27(1):36-48. doi: 10.1002/zoo.20159.
Seasonal fluctuation in serum concentrations of sex steroid (testosterone [T] and 17beta-estradiol [E(2)]) and thyroid (triiodothyronine [T(3)] and thyroxine [T(4)]) hormones was determined in captive Western fence lizards (Sceloporus occidentalis). Samples were collected from male and female breeding pairs weekly for a 4-month period after their emergence from artificial brumation. Circulating levels of E(2) corresponded with the expected vitellogenic and ovulatory cycles in females, and surprisingly, E(2) in males followed a similar pattern, indicating a possible role in breeding behavior. Serum T was elevated in male lizards for the first 6 weeks after emergence from brumation, possibly related to an increase in the onset of active spermatogenesis. Thyroid hormones showed little cyclical activity throughout the breeding period, with the exception of small increases of T(3) at weeks 8 and 16, possibly implying an active role of this hormone with ovulation in females. Overall, these baseline hormone data are not only useful in developing this animal as a laboratory reptile model for assessment of endocrine-mediated toxicity, but also of value for understanding herpetological endocrinology and for application in the conservation of threatened species. Zoo Biol 27:36-48, 2008. (c) 2007 Wiley-Liss, Inc.
在圈养的西部围栏蜥蜴（Sceloporus occidentalis）中测定了性类固醇激素（睾酮[T]和17β-雌二醇[E₂]）以及甲状腺激素（三碘甲状腺原氨酸[T₃]和甲状腺素[T₄]）血清浓度的季节性波动。在它们从人工冬眠中苏醒后的4个月期间，每周从雌雄繁殖对中采集样本。雌性蜥蜴体内E₂的循环水平与预期的卵黄生成和排卵周期相符，令人惊讶的是，雄性蜥蜴体内的E₂也呈现类似模式，表明其在繁殖行为中可能发挥作用。雄性蜥蜴从冬眠中苏醒后的前6周血清T升高，这可能与精子发生开始时的增加有关。在整个繁殖期，甲状腺激素几乎没有周期性活动，不过在第8周和第16周T₃有小幅升高，这可能意味着该激素在雌性排卵中发挥了积极作用。总体而言，这些基线激素数据不仅有助于将这种动物开发为用于评估内分泌介导毒性的实验室爬行动物模型，对于理解爬行动物内分泌学以及应用于濒危物种保护也具有价值。《动物园生物学》27:36 - 48，2008年。（c）2007威利 - 利斯公司。
