van Lunteren E, Haxhiu M A, Cherniack N S, Arnold J S
Department of Medicine, University Hospitals, Cleveland, Ohio.
J Appl Physiol (1985). 1988 Dec;65(6):2440-5. doi: 10.1152/jappl.1988.65.6.2440.
Studies in mammals have found that during breathing the triangularis sterni (TS) muscle regulates expiratory airflow and the end-expiratory position of the rib cage and furthermore that the respiratory activity of this muscle is influenced by a variety of chemical and mechanical stimuli. To assess the role of the TS during coughing and sneezing, electromyograms (EMGs) recorded from the TS were compared with EMGs of the transversus abdominis (TA) in eight pentobarbital-anesthetized dogs. During coughing induced by mechanically stimulating the trachea or larynx (n = 7 dogs), peak EMGs increased from 23 +/- 2 to 74 +/- 5 U (P less than 0.00002) for the TS and from 21 +/- 6 to 66 +/- 4 U (P less than 0.0002) for the TA. During sneezing induced by mechanically stimulating the nasal mucosa (n = 3 dogs), peak EMG of the TS increased from 10 +/- 3 to 66 +/- 7 U (P less than 0.005) and peak EMG of the TA increased from 10 +/- 2 to 73 +/- 7 U (P less than 0.02). For both muscles the shape of the EMG changed to an early peaking form during coughs and sneezes. Peak expiratory airflow during coughs of different intensity correlated more closely with peak TS EMG in three dogs and with peak TA EMG in four dogs; peak expiratory airflow during sneezes of different intensity correlated more closely with peak TS than TA EMG in all three animals. These results suggest that the TS is actively recruited during coughing and sneezing and that different neuromuscular strategies may be utilized to augment expiratory airflow.
对哺乳动物的研究发现，在呼吸过程中，胸骨三角肌（TS）调节呼气气流和胸廓的呼气末位置，此外，该肌肉的呼吸活动受多种化学和机械刺激的影响。为了评估TS在咳嗽和打喷嚏过程中的作用，在8只戊巴比妥麻醉的狗身上，将TS记录的肌电图（EMG）与腹横肌（TA）的EMG进行了比较。在通过机械刺激气管或喉部诱发咳嗽时（n = 7只狗），TS的EMG峰值从23±2增加到74±5 U（P<0.00002），TA的EMG峰值从21±6增加到66±4 U（P<0.0002）。在通过机械刺激鼻粘膜诱发打喷嚏时（n = 3只狗），TS的EMG峰值从10±3增加到66±7 U（P<0.005），TA的EMG峰值从10±2增加到73±7 U（P<0.02）。对于这两块肌肉，在咳嗽和打喷嚏时，EMG的形状都变为早期峰值形式。在3只狗中，不同强度咳嗽时的呼气气流峰值与TS的EMG峰值相关性更强，在4只狗中与TA的EMG峰值相关性更强；在所有3只动物中，不同强度打喷嚏时的呼气气流峰值与TS的EMG峰值的相关性比与TA的EMG峰值的相关性更强。这些结果表明，在咳嗽和打喷嚏时TS被积极募集，并且可能采用不同的神经肌肉策略来增强呼气气流。
