Collaborative Research: Oxygen Transport and Utilization During Sleep Apnea in Elephant Seals

该项目将联合收割机动物生理学与生物物理学和生物化学相结合，以检查象海豹在睡眠期间长时间自发屏气期间从整个动物到亚细胞水平的氧运输和消耗。这些动物独特的适应性包括增强的氧气储存和对心率、血流和组织代谢率的精确调节。这些适应的生理过程和生化机制与组织内氧气转移的基本原理以及海豹和鲸鱼非凡的潜水能力有关。 各种微创和非侵入性技术，包括血液/组织采样，血流测量和核磁共振成像/光谱，将允许研究这些海豹，而他们不受干扰地睡觉。这将允许：1）检查这些密封件在10分钟屏气过程中心率、心输出量和肌肉血流量的调节，2）测量屏气过程中血氧消耗的速率，3）检查随着血氧水平降低血液到肌肉的氧转移，4）测定肌红蛋白（肌肉中的储氧蛋白）的氧去饱和速率，5）检查肌肉中的代谢调节，如反映在高能磷酸盐、磷酸肌酸的消耗和乳酸盐的形成中，和6）检查肌红蛋白分子在肌细胞内的移动性。

This project will combine animal physiology with biophysics and biochemistry in order to examine oxygen transport and consumption from whole animal to subcellular levels during the prolonged, spontaneous breath-holds of elephant seals during sleep. Unique adaptations in these animals include enhanced oxygen storage and exquisite regulation of heart rate, blood flow and tissue metabolic rates. The physiological processes and biochemical mechanisms underlying these adaptations are relevant to the basic principles of oxygen transfer within tissues as well as to the remarkable diving abilities of seals and whales. A variety of minimally- and non-invasive techniques, including blood/tissue sampling, blood flow measurements, and nuclear magnetic resonance imaging/spectroscopy, will allow study of these seals while they sleep undisturbed. This will allow: 1) examination of the regulation of heart rate, cardiac output and muscle blood flow throughout the ten-minute breath-holds of these seals, 2) measurement of the rate of blood oxygen depletion throughout the breath-hold, 3) examination of blood-to-muscle oxygen transfer as the blood oxygen level decreases, 4) determination of the oxygen desaturation rate of myoglobin - the oxygen storage protein in muscle, 5) examination of metabolic regulation in muscle, as reflected in the depletion of the high-energy phosphate, phosphocreatine, and the formation of lactate, and 6) examination of the mobility of the myoglobin molecule within the muscle cell.