Courteix D, Bedu M, Fellmann N, Heraud M C, Coudert J
Laboratoire de Physiologie, Faculté de Médecine, Clermont-Ferrand, France.
J Appl Physiol (1985). 1993 Nov;75(5):2022-7. doi: 10.1152/jappl.1993.75.5.2022.
In the breath-hold model described by S. Godfrey and E. J. M. Campbell (Respir. Physiol. 5: 385-400, 1968), chemical and nonchemical stimuli are independent. Because these two factors are time dependent, the effect of each could not be measured by breath-holding time (BHT). The aim of this study is to dissociate chemical and nonchemical stimuli and to assess the effects of BHT and PCO2 on respiratory center output by measurement of occlusion pressure (P0.1) and mean inspiratory flow (VI). Nine well-trained divers (age 36.5 +/- 5.0 yr) took part in the study. Each subject had to hold his breath at 75% of vital capacity for 30, 50, and 70 s of BHT. Before each breath hold, the subject inspired successively two vital capacities of the same CO2-O2 gas mixture. P0.1 and VI were measured during the first reinspiration after the breath hold. For the same BHT, we observed good linear relationships between P0.1 or VI and alveolar PCO2. The slopes of these relationships increased with BHT. For alveolar PCO2 of > 50 Torr, P0.1 increased linearly with BHT. These results indicate that, during breath holding, chemical and nonchemical stimuli acted linearly on respiratory motoneuron activity, but they were not independent.
在S. 戈弗雷和E. J. M. 坎贝尔所描述的屏气模型中（《呼吸生理学》5: 385 - 400, 1968），化学刺激和非化学刺激是相互独立的。由于这两个因素都与时间有关，所以无法通过屏气时间（BHT）来衡量它们各自的作用。本研究的目的是区分化学刺激和非化学刺激，并通过测量阻断压力（P0.1）和平均吸气流量（VI）来评估屏气时间和二氧化碳分压对呼吸中枢输出的影响。九名训练有素的潜水员（年龄36.5 +/- 5.0岁）参与了该研究。每位受试者必须在肺活量的75%水平下屏气30、50和70秒。在每次屏气前，受试者依次吸入相同二氧化碳 - 氧气混合气体的两个肺活量。在屏气后的第一次再吸气过程中测量P0.1和VI。对于相同的屏气时间，我们观察到P0.1或VI与肺泡二氧化碳分压之间存在良好的线性关系。这些关系的斜率随屏气时间增加。对于肺泡二氧化碳分压> 50 Torr的情况，P0.1随屏气时间呈线性增加。这些结果表明，在屏气过程中，化学刺激和非化学刺激对呼吸运动神经元活动呈线性作用，但它们并非相互独立。
