ENDOCRINE RESPONSIVENESS IN HETEROTHERMY

候选人计划留在阿拉斯加大学， 研究他独特的动物模型，冬眠的北极地松鼠 帕氏黄鼠 这份奖励将使他能够增加他的时间 可用于研究的约为65%至85%。 因为 抗冻性的研究涉及技术和方法， 候选人没有接受过专门培训，收到RCDA 会特别有利，让他有时间与 其他机构的低温生物学专家 北极研究所 生物学完全支持候选人的工作，并提供了一个独特的 在环境方面的研究的适当情况， 设施;相对的地理隔离和小规模的 然而，研究所限制了互动的可能性，除非旅行 通过限制非研究责任来实现。 拟议的研究调查（一）之间的相互关系， 生殖内分泌系统与机体季节性变化的调控 温度（Tb的）在冬眠的哺乳动物，和（II）的机制，S。 parryii可以适应零度以下的Tb而不结冰。 目标涉及 繁殖功能和冬眠包括：（1）测量血浆 冬眠结束时的生殖激素水平;（2）CNS检测 对雄激素抑制冬眠的敏感性; nd（3）确定是否 血浆类固醇激素结合蛋白阻止这种抑制， 冬眠 与抗冻性相关的目的包括：（1）确定 对零度以下耐受性的限制和对来自抗冻动物的血液的测试 用于防冻剂和冷冻保护剂;（2）测量血液中的季节性变化 过冷点与血清蛋白和脂蛋白的关系;（3） 血液中的冰核因子，并确定地松鼠 消除这些，以避免冻结;（4）人工解冻， 过冷动物，以研究冷冻防御机制;和（5） 研究非颤抖性产热在稳定零度以下的作用 体温过低 这些实验应该阐明新的功能之间的关系 生殖内分泌系统和中枢神经系统对结核病的控制。 它们解决 生殖复发是如何开始的问题， 黑暗和冬眠时的周期性低温。 其他 实验研究的基本问题，显然独特的机制 哺乳动物的抗冻性，答案可能与 移植器官的冷冻保存和对严重低温的耐受性。

The candidate plans to remain at the University of Alaska to pursue research on his unique animal model, the hibernating arctic ground squirrel Spermophilus parryii. The award would enable him to increase his time available for research from approximately 65 to 85%. Because the investigation of freeze resistance involves techniques and approaches in which the candidate has not been specifically trained, receipt of an RCDA would be especially advantageous in allowing him time to interact with experts in cryobiology at other institutions. The Institute of Arctic Biology fully supports the candidate's work and offers a uniquely appropriate situation for the studies in terms of environment and facilities; the relative geographical isolation and small size of the Institute, however, limit the potential for interactions unless travel is made possible by limiting non-research responsibilities. The proposed research investigates (I) interrelationships between the reproductive endocrine system and control over seasonally changing body temperatures (Tb's) in hibernating mammals, and (II) mechanisms by which S. parryii can adopt subzero Tb's without freezing. Aims related to reproductive function and hibernation include: (1) measuring plasma reproductive hormone levels at the end of hibernation; (2) testing for CNS sensitivity to androgen inhibition of hibernation; nd (3) determining if plasma steroid hormone-binding proteins prevent such inhibition during hibernation. Aims related to freeze resistance include: (1) determining limits to subzero tolerance and testing blood from freeze-resisting animals for antifreeze and cryoprotectants; (2) measuring seasonal changes in blood supercooling points and serum proteins and lipoproteins; (3) identifying ice nucleation factors in blood and determining if ground squirrels eliminate these to avoid freezing; (4) artificially inoculating freezing in supercooled animals to investigate mechanisms of freeze defense; and (5) examining the role of nonshivering thermogenesis in stabilizing subzero hypothermia. These experiments should elucidate novel functional relationships between the reproductive endocrine system and CNS control over Tb. They address the question of how reproductive recrudescence begins during the constant darkness and periodic low body temperatures of hibernation. Other experiments investigate basic questions about apparently unique mechanisms of freeze resistance in mammals, answers to which may relate to cryopreservation of transplant organs and tolerance to severe hypothermia.