Legrand A, Wilson T A, De Troyer A
Laboratory of Cardiorespiratory Physiology, Brussels School of Medicine, and Chest Service, Erasme University Hospital, 1070 Brussels, Belgium.
J Appl Physiol (1985). 1998 Jul;85(1):198-203. doi: 10.1152/jappl.1998.85.1.198.
We have previously demonstrated in dogs that the change in airway opening pressure (DeltaPao) produced by isolated maximum activation of the parasternal intercostal or triangularis sterni muscle in a single interspace, the sternomastoids, and the scalenes is proportional to the product of muscle mass and the fractional change in muscle length per unit volume increase of the relaxed chest wall. In the present study, we have assessed the interactions between these muscles by comparing the DeltaPao obtained during simultaneous activation of a pair of muscles (measured DeltaPao) to the sum of the DeltaPao values obtained during their separate activation (predicted DeltaPao). Measured and predicted DeltaPao values were compared for the following pairs of muscles: the parasternal intercostals in two interspaces, the parasternal intercostals in one interspace and either the sternomastoids or the scalenes, two segments of the triangularis sterni, and the interosseous intercostals in two contiguous interspaces. For all these pairs, the measured DeltaPao was within approximately 10% of the predicted value. We therefore conclude that 1) the pressure changes generated by the rib cage muscles are essentially additive; and 2) measurements of the mass of a particular muscle and of its fractional change in length during passive inflation can be used to estimate the potential pressure-generating ability of the muscle during coordinated activity as well as during isolated activation.
我们之前在狗身上证明，单个肋间胸骨旁肌或胸骨三角肌、胸锁乳突肌和斜角肌的最大孤立激活所产生的气道开口压力变化（ΔPao）与肌肉质量以及放松胸壁单位体积增加时肌肉长度的分数变化的乘积成正比。在本研究中，我们通过比较一对肌肉同时激活时获得的ΔPao（测量的ΔPao）与它们单独激活时获得的ΔPao值之和（预测的ΔPao）来评估这些肌肉之间的相互作用。对以下几对肌肉比较了测量的和预测的ΔPao值：两个肋间的胸骨旁肋间肌、一个肋间的胸骨旁肋间肌与胸锁乳突肌或斜角肌、胸骨三角肌的两段以及两个相邻肋间的肋间内肌。对于所有这些肌肉对，测量的ΔPao在预测值的约10%范围内。因此，我们得出结论：1）胸廓肌肉产生的压力变化基本上是相加的；2）特定肌肉的质量及其在被动充气期间长度的分数变化的测量可用于估计肌肉在协调活动以及孤立激活期间产生压力的潜在能力。
