Cardio-respiratory recordings of hibernating animals

冬眠动物的心肺记录

• 批准号: RTI-2018-00006
• 负责人: Milsom, William
• 金额: $ 5.34万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Research Tools and Instruments
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=642197
• 关键词: Cardio; respiratory; recordings; hibernating; animals

The ability of mammals to hibernate is a dramatic example of phenotypic plasticity. Each year mammalian hibernators undergo a complex suite of morphological, physiological, and behavioral changes in preparation for environmental changes that lead to increased energy demands at a time of reduced energy supply. Hibernators avoid this conflict by entering extended bouts of torpor that range in duration from a few days to several weeks depending on the species. During torpor, basal metabolic rate can fall to as low as 1– 4% of euthermic (non-hibernating) levels and body temperature to within a few degrees above ambient temperature. The ability to enter torpor and to hibernate, is found throughout the class Mammalia and appears to involve differential expression of genes common to all mammals, rather than the induction of novel gene products unique to hibernating species. During hibernation, while most biochemical and physiological processes are dramatically slowed if not halted altogether, some critical functions continue to be precisely regulated. Breathing is one of these. Ventilation must still be regulated to match O2 consumption and CO2 excretion to metabolism, and blood levels of O2, CO2 and pH continue to be homeostatically maintained. We have been studying the cardio-respiratory adaptations of a variety of species of hibernating mammals and have made good progress in beginning to describe the mechanistic basis of their tolerance to cold and hypoxia (low levels of O2). These results give insight not only into the hibernating phenotype but into the basis of hypothermic respiratory arrest in non-hibernating species, including humans. One of our biggest challenges has been obtaining data during the processes of entrance into, and arousal from hibernation. Animals are very sensitive to disturbance at this time making traditional forms of data gathering impossible. There are several companies now commercially making radiotelemetry units at reasonable prices that would allow us to gather data from implanted transmitters removing the need for handling animals and for hard-wired electrodes and cannulae that restrict animal movement. Purchase of this equipment would allow us to gather information during these transition phases that previously has been unavailable.

哺乳动物的冬眠能力是表型可塑性的一个引人注目的例子。每年哺乳动物冬眠经历一系列复杂的形态，生理和行为变化，以准备环境变化，导致能量需求增加，同时能量供应减少。冬眠者通过进入持续时间从几天到几周不等的长时间休眠来避免这种冲突。在冬眠期间，基础代谢率可以下降到正常体温（非冬眠）水平的1- 4%，体温可以下降到比环境温度高几度。进入休眠状态和冬眠的能力在整个哺乳动物纲中都有发现，似乎涉及所有哺乳动物共有的基因的差异表达，而不是诱导冬眠物种特有的新基因产物。在冬眠期间，虽然大多数生化和生理过程即使没有完全停止，也会大大减慢，但一些关键功能仍然受到精确的调节。呼吸就是其中之一。仍然必须调节通气以使O2消耗和CO2排泄与代谢相匹配，并且O2、CO2和pH的血液水平继续保持稳态。我们一直在研究各种冬眠哺乳动物的心肺适应，并在开始描述它们对寒冷和缺氧（低水平的O2）的耐受性的机制基础方面取得了良好的进展。这些结果不仅提供了对冬眠表型的深入了解，而且也为非冬眠物种（包括人类）的低温呼吸停止提供了依据。我们最大的挑战之一是在进入冬眠和从冬眠中唤醒的过程中获得数据。动物对干扰非常敏感，这使得传统形式的数据收集变得不可能。现在有几家公司以合理的价格生产无线电遥测装置，使我们能够从植入的发射器中收集数据，从而消除了处理动物以及限制动物运动的硬连线电极和套管的需要。购买这些设备将使我们能够在这些过渡阶段收集以前无法获得的信息。