Greenleaf J E, Van Beaumont W, Brock P J, Morse J T, Mangseth G R
Am J Physiol. 1979 Mar;236(3):R206-14. doi: 10.1152/ajpregu.1979.236.3.R206.
Plasma volume (PV) and electrolyte shifts were measured before and for 60 min after a continuous peak oxygen uptake (VO2 peak) test in four men (26-45 yr) on a bicycle ergometer. Mean (+/-SE) sitting VO2peak (3.16 +/- 0.32 1/min) was the same as supine VO2peak (3.13 +/- 0.33 1/min). In recovery (R + 1.5 min), mean PV had decreased by 477 ml (-16.1%, P less than 0.05) in the sitting and by 548 ml (-17.6%, P less than 0.05) in the supine positions, whereas total osmolality increased progressively with its peak at R + 3.5 min. The percentage losses of protein, total Ca2+, and ionized Cai2+ were about half as great as the percentage loss in PV, indicating a selective retention of these constituents. Calculated osmolality (sigma Na+, K+, Cl-, Cai2+) returned to control levels within 1.5 min after sitting exercise but required about 15 min after supine exercise. These small increases in protein concentration were not likely to significantly aid restitution of plasma volume and the ions were probably in equilibrium across the capillary membrane. So a change in hydrostatic and/or systemic blood pressures most likely provided the force for restitution of plasma volume.
在自行车测力计上，对4名男性（26 - 45岁）进行持续峰值摄氧量（VO₂峰值）测试前后，测量了血浆容量（PV）和电解质变化，持续时间为60分钟。平均（±标准误）坐姿VO₂峰值（3.16±0.32升/分钟）与仰卧位VO₂峰值（3.13±0.33升/分钟）相同。在恢复阶段（R + 1.5分钟），坐姿时平均PV减少了477毫升（-16.1%，P < 0.05），仰卧位时减少了548毫升（-17.6%，P < 0.05），而总渗透压逐渐升高，在R + 3.5分钟时达到峰值。蛋白质、总Ca²⁺和游离Ca²⁺的损失百分比约为PV损失百分比的一半，表明这些成分有选择性的保留。计算渗透压（σNa⁺、K⁺、Cl⁻、Ca²⁺）在坐姿运动后1.5分钟内恢复到对照水平，但仰卧位运动后需要约15分钟。蛋白质浓度的这些小幅增加不太可能显著有助于血浆容量的恢复，离子可能在毛细血管膜两侧处于平衡状态。因此，静水压和/或全身血压的变化最有可能为血浆容量的恢复提供动力。
