Duffin J, Bechbache R R, Goode R C, Chung S A
Respir Physiol. 1980 Apr;40(1):93-105. doi: 10.1016/0034-5687(80)90007-9.
The sensitivity of the ventilatory response to carbon dioxide in hyperoxia during light (25 W) exercise was compared to that at rest in 14 volunteers. The method used was that of rebreathing. Two factors were found to produce artefactual changes in the slope of the response during exercise. First, breath-by-breath response lines showed that the maximum limit of ventilation was reached in 3 volunteers before the end of rebreathing, despite the low exercise load. The inclusion of such breaths in the calculation of the slope of the response could produce an artefactual decrease in slope. Second, most of the response lines showed an increase in their slope during exercise. However, a model of rebreathing in exercise showed that an increase in sensitivity could be the result of variation in the difference between end-tidal and central chemoreceptor carbon dioxide levels during exercise. A criterion derived from the model, proportional to the variation in this difference, was found to be correlated with the increase in sensitivity from rest to exercise. It was therefore concluded that the sensitivity of the ventilatory response to carbon dioxide during light exercise is unchanged from that at rest.
在14名志愿者中，比较了在高氧环境下轻度（25瓦）运动时通气对二氧化碳反应的敏感性与静息时的敏感性。采用的方法是重复呼吸法。发现有两个因素会在运动期间使反应斜率产生人为变化。首先，逐次呼吸反应线显示，尽管运动负荷较低，但有3名志愿者在重复呼吸结束前就达到了通气的最大极限。将此类呼吸纳入反应斜率的计算可能会导致斜率出现人为降低。其次，大多数反应线在运动期间显示出斜率增加。然而，运动中的重复呼吸模型表明，敏感性增加可能是运动期间终末潮气与中枢化学感受器二氧化碳水平差异变化的结果。从该模型得出的一个与这种差异变化成比例的标准，被发现与从静息到运动时敏感性的增加相关。因此得出结论，轻度运动期间通气对二氧化碳反应的敏感性与静息时相同，没有变化。
