Dauphin-Villemant C, Xavier F
Ecole Normale Supérieure, CNRS-UA 686, Paris, France.
Gen Comp Endocrinol. 1987 Sep;67(3):292-302. doi: 10.1016/0016-6480(87)90183-3.
This work was designed to study nychthemeral variations of plasma corticosterone and aldosterone in captive female lizards Lacerta vivipara. In preliminary experiments, the possible alterations of plasma corticosteroids by various stress factors were researched. A prolonged blood sampling (up to 8 min) did not alter plasma corticosterone levels but a significant increase of plasma aldosterone levels was observed. Confinement (1 or 18 hr) in small individual cages before blood collection resulted in a significant increase of both corticosterone and aldosterone. Whatever the period investigated (vitellogenesis, gestation, 2 months after parturition), plasma corticosterone levels showed a unimodal daily rhythm correlated with the activity of the females in the laboratory. No shift of the peak was observed according to season but the mean minimal and maximal levels were lower during vitellogenesis than during the other periods tested. Nychthemeral variations of plasma aldosterone levels were similar to those of corticosterone but of lower amplitude. Adrenal response to a short confinement (less than 1 hr) before blood sampling varied during a 24-hr period (period tested: vitellogenesis). Only minimal levels of corticosteroids were significantly increased. The possible effects of a long duration of captivity under optimal thermal conditions are discussed.
本研究旨在探讨圈养雌性胎生蜥蜴血浆皮质酮和醛固酮的昼夜变化。在初步实验中，研究了各种应激因素对血浆皮质类固醇的可能影响。长时间采血（长达8分钟）并未改变血浆皮质酮水平，但观察到血浆醛固酮水平显著升高。采血前在小个体笼中禁闭（1或18小时）导致皮质酮和醛固酮均显著增加。无论研究的时期如何（卵黄发生期、妊娠期、产后2个月），血浆皮质酮水平均呈现与实验室中雌性活动相关的单峰昼夜节律。未观察到峰值随季节的变化，但卵黄发生期的平均最低和最高水平低于其他测试时期。血浆醛固酮水平的昼夜变化与皮质酮相似，但幅度较小。在24小时期间（测试时期：卵黄发生期），采血前短时间禁闭（少于1小时）引起的肾上腺反应有所不同。只有最低水平的皮质类固醇显著增加。讨论了在最佳热条件下长期圈养的可能影响。
