Physiological Mechanisms of Anoxic Tolerance

耐缺氧的生理机制

• 批准号: 9420017
• 负责人: Donald Jackson
• 金额: $ 31.5万
• 依托单位: Brown University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-04-01 至 1998-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9420017&HistoricalAwards=false
• 关键词: Physiological; Mechanisms; Anoxic; Tolerance

9420017 Jackson The object of this investigation is to understand how a specially adapted vertebrate animal, the freshwater turtle, is able to survive long periods without oxygen. Based on this knowledge, the long-term goal is to uncover fundamental principles of cellular and organismal function related to this problem. Several experimental approaches will be utilized. First, at the whole animal level, the distribution and excretion of key body fluid substances, lactic acid, CO2 and chloride ion will be determined using injected radioactively-labelled compounds. These compounds are all important in determining acid-base balance during anoxia and these experiments will clarify aspects of the important homeostatic function of blood pH regulation in these animals. Second, heart function in these animals will be studied because of the usual sensitivity of this organ to anoxia. Mechanical properties of small strips of cardiac muscle will be studied under conditions that simulate the anoxic state of the living animal, utilizing known changes in blood pH, ion concentrations, and catecholamine levels in our test solutions. Third, the response of skeletal muscle to long-term anoxia will be studied both in the intact animal and in isolated pieces of muscle using the technique of magnetic resonance spectroscopy. Dr. Jackson's object in these experiments is to assess the cellular energetics, the capacity to do work, and the recovery from activity in the muscles of this animal in the absence of oxygen. The remarkable characteristics of an animal specialist such as the turtle and its organ systems make it an ideal preparation for understanding basic principles of cellular metabolism and energetics in response to anoxia and acidosis. Of broader significance is understanding how adaptations revealed at the cell or organ system level incorporate into the integrative behavior of the intact animal. ***

小行星9420017杰克逊 这项调查的目的是了解一种特别适应的脊椎动物，淡水龟，如何能够在没有氧气的情况下长期生存。 基于这些知识，长期目标是揭示与此问题相关的细胞和有机体功能的基本原理。 将使用几种实验方法。 首先，在整个动物水平上，将使用注射的放射性标记化合物测定关键体液物质、乳酸、CO2和氯离子的分布和排泄。 这些化合物都是重要的，在缺氧期间确定酸碱平衡，这些实验将澄清这些动物的血液pH值调节的重要稳态功能方面。 第二，由于这些动物的心脏通常对缺氧很敏感，因此将对这些动物的心脏功能进行研究。 将在模拟活体动物缺氧状态的条件下，利用我们测试溶液中血液pH值、离子浓度和儿茶酚胺水平的已知变化，研究小条心肌的机械特性。 第三，骨骼肌对长期缺氧的反应将在完整的动物和分离的肌肉块中使用磁共振波谱技术进行研究。 杰克逊博士在这些实验中的目的是评估细胞能量学，做功能力，以及在没有氧气的情况下肌肉活动的恢复。 动物专家的显着特征，如海龟及其器官系统，使其成为了解细胞代谢和能量学基本原理的理想准备，以应对缺氧和酸中毒。 更广泛的意义是理解在细胞或器官系统水平上揭示的适应如何融入完整动物的整合行为。 ***