SLEEP APNEA IN SEALS: METABOLIC IMPLICATIONS

这项提案概述了第一个系统的研究代谢 呼吸暂停对哺乳动物物种的影响， 在睡眠时承受长时间的屏气。 的 北方象海豹幼崽经历缺氧条件下， 陆地哺乳动物无法忍受的睡眠呼吸暂停。 作为 无论是幼崽还是成年海豹， 呼吸暂停长达30分钟。 这些发现将使基本的生物学 与人类和其他哺乳动物的医学比较， 在睡眠中表现出异常的呼吸模式。 初步研究表明，幼年海豹的睡眠呼吸暂停是 一种非稳态条件， 心率变化、血液化学变化和底物 利用率模式与所见模式有很大不同 在睡觉的陆地哺乳动物中， 海豹潜水时的样子 这项研究有三个主要目标： 1)睡眠呼吸暂停的基本代谢特征 年轻海豹的现象。 2)相似性的说明 睡眠呼吸暂停和代谢性呼吸暂停 屏气潜水时的规则。3)调查结果的应用 睡眠呼吸暂停期间缺氧耐受性的比较研究， 陆地物种的慢性缺氧。 研究将包括：测量血气变化，心率 呼吸暂停期间的血液pH值;随着血浆 通过需氧和厌氧途径承载的底物（葡萄糖， 脂肪酸，乳酸盐）;检查次黄嘌呤的代谢 作为缺氧的临床标志;随着血流的变化 模式、红细胞压积调节和外周器官灌注， 功能;检查组织的生化适应， 缺氧 对强迫潜水和无约束潜水的类似研究 海豹将提供睡眠呼吸暂停与 在海豹清醒和潜水的时候所经历的。 最后利用 公认的改善中枢性睡眠呼吸暂停的临床技术 人类的模式（例如氧气补充），将努力 用于改变和进一步表征睡眠呼吸暂停模式， 密封件. 该提案将允许对睡眠进行基本调查 呼吸暂停的密封最好用于生物和医疗 比较研究

This proposal outlines the first systematic study of the metabolic impact of apnea on a mammalian species that routinely withstands long duration breath-holds while sleeping. The northern elephant seal pup experiences hypoxic conditions during sleep apnea that can not be withstood by terrestrial mammals. As pups and adults, these seals are capable of long duration sleep apnea of up to 30 minutes. The findings will allow basic biological and medical comparisons to humans and other mammals that exhibit abnormal respiratory patterns during sleep. Preliminary studies suggest that sleep apnea in the juvenile seal is a non-steady state condition during which hypoxia tolerance, heart rate changes, blood chemistry variations and substrate utilization patterns are significantly different from patterns seen in sleeping terrestrial mammals and remarkably similar to those seen when seals dive. This study has three major objectives: 1) The basic metabolic characterization of the sleep apnea phenomenon in juvenile seals. 2) The elucidation of similarities between hypoxia tolerance during sleep apnea and metabolic regulation during breath-hold diving. 3) Application of the findings to comparative studies of hypoxia tolerance during sleep apnea or chronic hypoxia in terrestrial species. Studies will include: Measuring shifts in blood gases, heart rate and blood pH during apnea; following the metabolism of plasma borne substrates through aerobic and anaerobic pathways (glucose, fatty acids, lactate); examining the metabolism of hypoxanthine as a clinical marker of hypoxia; following changes in blood flow pattern, hematocrit regulation and peripheral organ perfusion and function; examining tissues for biochemical adaptations to hypoxia. Similar studies on both forced and unrestrained diving seals will provide the data for comparing sleep apnea to the apnea experienced while the seal is awake and diving. Finally, using accepted clinical techniques for modifying central sleep apnea patterns in humans (e.g. oxygen supplementation), efforts will be made to modify and further characterize sleep apnea patterns in seals. This proposal will allow this basic investigation of sleep apnea in the seal to best be used for biological and medical comparative studies.