Sugarbaker D J, Rattan S, Goyal R K
Am J Physiol. 1984 Nov;247(5 Pt 1):G515-9. doi: 10.1152/ajpgi.1984.247.5.G515.
We examined the mechanical activity of the longitudinal and circular muscles of the esophagus at three different levels (9, 5, and 1 cm above the lower esophageal sphincter) during peristalsis induced by swallows or vagal stimulation in anesthetized opossums with miniature strain gauges applied in the axis of muscle fibers. The onset of longitudinal muscle contraction occurred in an aboral sequence with swallows but simultaneously with vagal stimulation. The speed of longitudinal muscle activation with swallows was 7.6 +/- 1.7 cm/s. Circular muscle contraction occurred in an aboral sequence with vagal stimulation and swallowing with speeds of 4.1 +/- 0.8 and 2.3 +/- 0.1 cm/s, respectively. Longitudinal muscle contracted before the circular muscle at all sites. The duration of longitudinal muscle contraction increased aborally (P less than 0.05) with swallowing or vagal stimulation. These studies show that 1) during swallowing, esophageal longitudinal and circular smooth muscle contract in a sequential fashion, 2) the longitudinal muscle sequential contraction is due to central mechanisms, whereas circular muscle sequential contraction may be due to both central and peripheral mechanisms, and 3) peripheral neuromuscular mechanisms produce regional differences in the duration of longitudinal muscle contraction.
我们在麻醉的负鼠身上，通过在肌纤维轴向上应用微型应变仪，研究了在吞咽或迷走神经刺激诱发蠕动期间，食管三个不同水平（食管下括约肌上方9厘米、5厘米和1厘米处）的纵行肌和环行肌的机械活动。吞咽时纵行肌收缩从口端向肛端依次发生，但迷走神经刺激时纵行肌收缩同时发生。吞咽时纵行肌激活速度为7.6±1.7厘米/秒。迷走神经刺激和吞咽时环行肌收缩均从口端向肛端依次发生，速度分别为4.1±0.8厘米/秒和2.3±0.1厘米/秒。在所有部位，纵行肌均先于环行肌收缩。吞咽或迷走神经刺激时，纵行肌收缩持续时间向肛端增加（P<0.05）。这些研究表明：1）吞咽时，食管纵行肌和环行平滑肌依次收缩；2）纵行肌的依次收缩归因于中枢机制，而环行肌的依次收缩可能归因于中枢和外周机制；3）外周神经肌肉机制导致纵行肌收缩持续时间存在区域差异。
