Castellini M A, Costa D P, Huntley A
Am J Physiol. 1986 Aug;251(2 Pt 2):R429-31. doi: 10.1152/ajpregu.1986.251.2.R429.
Hematocrit (Hct) levels were found to increase throughout long-duration sleep apnea in the northern elephant seal pup. Breath holds ranging from 4 to greater than 11 min were sampled. Blood collected from the extradural intravertebral vein showed an increase in Hct from 55.6 to 63.1% with the peak value occurring within 1 min of the end of apnea. Plasma lactate did not change throughout the breath hold. Previous observations of changing Hct levels in seals were made on animals diving naturally, and consequently the effects of exercise could not be separated from those of apnea. The results of this study demonstrate that the rise in Hct is produced quickly upon apnea, occurs without significant levels of hypoxic metabolism, and does not depend on exercise.
研究发现，北象海豹幼崽在长时间睡眠呼吸暂停期间，血细胞比容（Hct）水平会升高。对时长从4分钟到超过11分钟的屏气进行了采样。从硬脊膜内椎静脉采集的血液显示，血细胞比容从55.6%升至63.1%，峰值出现在呼吸暂停结束后1分钟内。在整个屏气过程中，血浆乳酸水平没有变化。之前对海豹血细胞比容水平变化的观察是在自然潜水的动物身上进行的，因此无法将运动的影响与呼吸暂停的影响区分开来。这项研究的结果表明，血细胞比容的升高在呼吸暂停后迅速出现，在没有显著低氧代谢水平的情况下发生，并且不依赖于运动。
