Seasonal changes in thermoregulatory responses to hypoxia in the Eastern chipmunk (Tamias striatus)
Seasonal changes in thermoregulatory responses to hypoxia in the Eastern chipmunk (Tamias striatus)
复制标题
东部花栗鼠（Tamias striatus）对缺氧的体温调节反应的季节性变化
DOI：
10.1242/jeb.027094
复制
发表时间：
2009
影响因子：
2.8
通讯作者：
G. Tattersall
中科院分区：
文献类型：
--
作者：
D. Levesque;G. Tattersall
已知哺乳动物异温动物比恒温动物更能耐受低氧水平。然而，异温动物表现出极端的季节性，在日常的异温和迟钝的表达。由于缺氧会抑制哺乳动物的体温（Tb）和新陈代谢，因此有兴趣了解能够冬眠的物种的正常体温动物的季节性比较是否会产生反映缺氧耐受性季节性变化的缺氧反应变化。所研究的物种，东方花栗鼠（Tamias striatus，Linnaeus 1758），已知只在冬季进入休眠状态。为了测试缺氧（9.9千帕）的代谢和体温调节反应的季节性差异，流通呼吸测定法被用来比较耗氧量，最小热导率和Tb在固定的环境温度（Ta）条件下，而热梯度被用来评估选定的Ta和Tb在缺氧，在夏季和冬季驯化的动物。在含氧量正常、体温正常的动物中，没有观察到季节之间的静息代谢或热传导差异。提供一个选择的Ta在缺氧的动物衰减的缺氧下降Tb在两个季节，这表明，报告下降Tb在缺氧是不完全表现在行为途径负责在花栗鼠的体温调节。相反，Tb在缺氧往往是更多变的，并依赖于Ta和季节。虽然Tb在两个季节的缺氧下降，减少较少，在冬季没有相应的代谢减少，表明冬季花栗鼠更耐缺氧比夏季动物。
SUMMARY Mammalian heterotherms are known to be more tolerant of low oxygen levels than homeotherms. However, heterotherms demonstrate extreme seasonality in daily heterothermy and torpor expression. Because hypoxia depresses body temperature (Tb) and metabolism in mammals, it was of interest to see if seasonal comparisons of normothermic animals of a species capable of hibernation produce changes in their responses to hypoxia that would reflect a seasonal change in hypoxia tolerance. The species studied, the Eastern chipmunk (Tamias striatus, Linnaeus 1758), is known to enter into torpor exclusively in the winter. To test for seasonal differences in the metabolic and thermoregulatory responses to hypoxia (9.9 kPa), flow-through respirometry was used to compare oxygen consumption, minimum thermal conductance and Tb under fixed ambient temperature (Ta) conditions whereas a thermal gradient was used to assess selected Ta and Tb in response to hypoxia, in both summer- and winter-acclimated animals. No differences were observed between seasons in resting metabolism or thermal conductance in normoxic, normothermic animals. Providing the animals with a choice of Ta in hypoxia attenuated the hypoxic drop in Tb in both seasons, suggesting that the reported fall in Tb in hypoxia is not fully manifested in the behavioural pathways responsible for thermoregulation in chipmunks. Instead, Tb in hypoxia tends to be more variable and dependent on both Ta and season. Although Tb dropped in hypoxia in both seasons, the decrease was less in the winter with no corresponding decrease in metabolism, indicating that winter chipmunks are more tolerant to hypoxia than summer animals.
性别对缺氧大鼠体温调节和生存的影响。
DOI：
10.1111/j.1440-1681.1998.tb02196.x
发表时间：
1998
影响因子：
2.9
作者：
Wood,SC;Stabenau,EK
通讯作者：
Stabenau,EK
DOI：
10.1016/0305-0491(95)02045-4
发表时间：
1996
期刊：
Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology
影响因子：
--
作者：
S. C. Wood;Rayna Gonzales
通讯作者：
S. C. Wood;Rayna Gonzales
DOI：
10.1152/ajpregu.00260.2005
发表时间：
2005-11-01
影响因子：
2.8
作者：
Ma, YL;Zhu, XW;Drew, KL
通讯作者：
Drew, KL