Recovery periods during repeated stress impact corticosterone and behavioral responses differently in house sparrows
Recovery periods during repeated stress impact corticosterone and behavioral responses differently in house sparrows
复制标题
DOI：
10.1016/j.yhbeh.2019.04.009
复制
发表时间：
2019-06-01
影响因子：
3.5
通讯作者：
Romero, L. Michael
中科院分区：
文献类型：
--
作者：
Gormally, Brenna M. G.;Ramos, Sarah;Romero, L. Michael
许多研究表明，慢性应激会对多种生物体的生理和行为产生负面影响。这些变化是否会永久性地改变动物的功能，或者它们是否可以逆转，这一点还有待深入研究。在这项研究中，我们使用野生捕获的家雀(Passer Home Ticus)来评估恢复期如何影响最初四天和随后四天重复应激源的生理和行为影响。鸡被随机分配到恢复组，在两组应激源(翻笼和敲笼)之间经历0、24或72小时的恢复。我们通过量化基线和应激诱导的皮质酮以及负反馈强度来测量下丘脑-垂体-肾上腺(HPA)轴的调节。我们还使用新恐惧症试验来评估行为，以衡量鸟类如何改变它们对新对象的态度和它们的总体活动，在实验之前、恢复时间之后和最后4天的应激源之后评估行为和皮质酮反应。我们发现，与实验前的样本相比，经历了24小时恢复的鸟类减少了应激诱导的皮质酮，但增强了负反馈。此外，4天的应激源足以显著减少接近新对象的潜伏期；然而，随着更长的恢复期，实验前的水平恢复了。最后，恢复时间对第二个4天应激源的反应没有显著影响。我们的结果表明，短暂的恢复期可以部分改善反复应激的荷尔蒙和行为影响。
A number of studies have shown that chronic stress can negatively impact both physiology and behavior in a variety of organisms. What has yet to be extensively explored is whether these changes permanently alter an animal's functioning, or if they can be reversed. In this study, we used wild-caught house sparrows (Passer domesticus) to assess how recovery periods influence the physiological and behavioral impacts of an initial four days and subsequent four days of repeated stressors. Birds were randomly assigned to a recovery group and either experienced 0, 24, or 72 h of recovery between the two sets of stressors (cage rolling and cage tapping). We measured the regulation of the hypothalamic pituitary adrenal (HPA) axis by quantifying baseline and stress-induced corticosterone as well as negative feedback strength. We also assessed behavior using neophobia trials to measure how birds altered their approach towards novel objects and their overall activity, Both behavior and corticosterone responses were assessed before the experiment, after the recovery time, and following the final 4 days of stressors. We found that birds that experienced 24 h of recovery had reduced stress-induced corticosterone, but enhanced negative feedback relative to the pre-experiment sample. Additionally, 4 days of stressors was enough to significantly reduce approach latency towards novel objects; however, pre-experiment levels returned with longer periods of recovery. Finally, recovery time did not significantly influence responses to the second 4 days of stressors. Our results indicate that brief recovery periods partially ameliorate the hormonal and behavioral effects of repeated stress.