Lopata M, Onal E, Ginzburg A S
J Appl Physiol Respir Environ Exerc Physiol. 1983 Feb;54(2):475-82. doi: 10.1152/jappl.1983.54.2.475.
We investigated the respiratory muscle contribution to inspiratory load compensation by measuring diaphragmatic and intercostal electromyograms (EMGdi and EMGic), transdiaphragmatic pressure (Pdi), and thoracoabdominal motion during CO2 rebreathing with and without 15 cmH2O X l-1 X s inspiratory flow resistance (IRL) in normal sitting volunteers. During IRL compared with control, Pdi measured during airflow and during airway occlusion increased for a given change in CO2 partial pressure and EMGdi, and there was a greater decrease in abdominal (AB) end expiratory anteroposterior dimensions with increased expiratory gastric pressure (Pga), this leading to an inspiratory decline in Pga with outward AB movement, indicating a passive component to the descent of the abdomen-diaphragm. The response of EMGic to IRL was similar to that of EMGdi, though rib cage (RC)-Pga plots did infer intercostal muscle contribution. We conclude that during CO2 rebreathing with IRL there is improved diaphragmatic neuromuscular coupling, the prolongation of inspiration promoting a force-velocity advantage, and increased AB action serving to optimize diaphragm length and configuration, as well as to provide its own passive inspiratory action. Intercostal action provides increased assistance also. Therefore, compensation for inspiratory resistive loads results from the combined and integrated effort of all respiratory muscle groups.
我们通过测量正常坐姿志愿者在有和没有15 cmH₂O·L⁻¹·s吸气气流阻力（IRL）的情况下进行二氧化碳再呼吸时的膈肌和肋间肌肌电图（EMGdi和EMGic）、跨膈压（Pdi）以及胸腹运动，研究了呼吸肌对吸气负荷补偿的贡献。与对照组相比，在IRL期间，对于给定的二氧化碳分压变化，气流期间和气道阻塞期间测量的Pdi以及EMGdi均增加，并且随着呼气时胃内压（Pga）升高，腹部（AB）呼气末前后径的减小幅度更大，这导致随着AB向外移动Pga出现吸气性下降，表明腹部 - 膈肌下降存在被动成分。EMGic对IRL的反应与EMGdi相似，尽管胸廓（RC） - Pga图确实推断出肋间肌的贡献。我们得出结论，在有IRL的二氧化碳再呼吸期间，膈肌神经肌肉耦合得到改善，吸气延长促进了力 - 速度优势，AB动作增加有助于优化膈肌长度和形态，并提供其自身的被动吸气动作。肋间肌动作也提供了更多辅助。因此，对吸气阻力负荷的补偿是所有呼吸肌群共同综合作用的结果。
