Thomas S N, Schroeder T, Secher N H, Mitchell J H
Department of Anesthesia, Rigshospitalet, University of Copenhagen, Denmark.
J Appl Physiol (1985). 1989 Aug;67(2):744-8. doi: 10.1152/jappl.1989.67.2.744.
Cerebral blood flow (CBF) in humans was measured at rest and during dynamic exercise on a cycle ergometer corresponding to 56% (range 27-85) of maximal O2 uptake (VO2max). Exercise bouts were performed by 16 male and female subjects, lasted 15 min each, and were carried out in a semisupine position. CBF (133Xe clearance) was expressed as the initial slope index (ISI) and as the first compartment flow (F1). CBF at rest [ISI, 58 (range 45-73); F1, 76 (range 55-98) ml.100 g-1.min-1] increased during exercise [ISI to 79 (57-94) and F1 to 118 (75-164) ml.100 g-1.min-1, P less than 0.01]. CBF did not differ significantly between work loads from 32 (24-33) to 86% (74-96) of VO2max (n = 10). During exercise, mean arterial pressure increased from 84 (60-100) to 101 (78-124) Torr (P less than 0.01) and PCO2 remained unchanged [5.1 (4.6-5.6) vs. 5.4 (4.4-6.3) kPa, n = 6]. These results demonstrate a median increase of 31% (0-87) in CBF by ISI and a median increase of 58% (0-133) in CBF by F1 during dynamic exercise in humans.
在静息状态以及在与最大摄氧量（VO₂max）的56%（范围为27%-85%）相对应的自行车测力计上进行动态运动期间，对人体的脑血流量（CBF）进行了测量。16名男性和女性受试者进行了运动试验，每次运动持续15分钟，且在半仰卧位进行。CBF（¹³³Xe清除率）以初始斜率指数（ISI）和第一室流量（F1）表示。静息时的CBF[ISI为58（范围45-73）；F1为76（范围55-98）ml·100g⁻¹·min⁻¹]在运动期间增加[ISI升至79（57-94），F1升至118（75-164）ml·100g⁻¹·min⁻¹，P<0.01]。在VO₂max的32%（24%-33%）至86%（74%-96%）的工作负荷之间，CBF无显著差异（n = 10）。运动期间，平均动脉压从84（60-100）Torr升至101（78-124）Torr（P<0.01），而PCO₂保持不变[5.1（4.6-5.6）kPa对5.4（4.4-6.3）kPa，n = 6]。这些结果表明，在人体动态运动期间，CBF通过ISI的中位数增加了31%（0%-87%），通过F1的中位数增加了58%（0%-133%）。
