Fitting J W, Chartrand D A, Bradley T D, Killian K J, Grassino A
J Appl Physiol (1985). 1987 Apr;62(4):1665-70. doi: 10.1152/jappl.1987.62.4.1665.
The respiratory sensations evoked by added inspiratory loads are currently thought to be largely mediated by the activity of the inspiratory muscles. Because of the differences in proprioceptors and in afferent and efferent innervations among the inspiratory muscles, we hypothesized that the sensation evoked by a given load would be different when the motor command is directed mainly to rib cage muscles or mainly to the diaphragm. To test this hypothesis, we studied six normal subjects breathing against several inspiratory resistances while emphasizing the use of rib cage muscles, or the diaphragm, or a combination of both. At the end of 10 loaded breaths the subjects rated the perceived magnitude of inspiratory effort on a Borg scale. A linear and unique relationship (r = 0.96 +/- 0.02; P less than 0.001) was found between the sensation and esophageal pressure (Pes) in the three thoracoabdominal breathing patterns. We conclude that the level of Pes, whether generated mainly by the rib cage muscles or the diaphragm, is the main variable related to the sensation of inspiratory effort under external inspiratory loads.
目前认为，额外吸气负荷所诱发的呼吸感觉在很大程度上是由吸气肌的活动介导的。由于吸气肌之间本体感受器以及传入和传出神经支配存在差异，我们推测，当运动指令主要指向胸廓肌肉或主要指向膈肌时，给定负荷所诱发的感觉会有所不同。为了验证这一假设，我们研究了六名正常受试者在对抗几种吸气阻力呼吸时的情况，同时分别强调使用胸廓肌肉、膈肌或两者结合。在进行10次负荷呼吸结束时，受试者根据Borg量表对所感知的吸气努力程度进行评分。在三种胸腹呼吸模式中，均发现感觉与食管压力（Pes）之间存在线性且独特的关系（r = 0.96 ± 0.02；P < 0.001）。我们得出结论，无论是主要由胸廓肌肉还是膈肌产生的Pes水平，都是与外部吸气负荷下吸气努力感觉相关的主要变量。
