The movements of the food in the œsophagus / by W.B. Cannon and A. Moser.

  • Walter Bradford Cannon
Date:
[1898?]
Catalogue details

Licence: Public Domain Mark

Credit: The movements of the food in the œsophagus / by W.B. Cannon and A. Moser. Source: Wellcome Collection.

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    CESOPHAGUS. By W. B. CANNON and A. MOSER. [Ft 'om the Laboratory of Physiology in the Harvard Medical School.’] THE movements of deglutition, in common with many other physiological processes, were explained by the older physiolo¬ gists on anatomical grounds. Thus Magendie 1 divided the act into three parts, corresponding to the anatomical regions of the mouth, pharynx, and oesophagus. The muscles of each of these divisions were considered the active agents in propelling the food onward. The function of moving the mass to the pharynx was variously ascribed to the tongue itself, to the mylohyoid muscles, and to gravity. For the second part, the movement through the pharynx, there was more unanimity of opinion, since the constrictors, espe¬ cially the middle and lower, were evidently concerned. Direct observations on the movement of swallowed masses in the oesophagus were first made by Mosso.2 The oesophagus of a dog was laid bare and a transverse incision made through it, or a piece of it excised. A small wooden ball was placed in the canal below the excised part, and the animal was then stimulated to swallow. One or two seconds after the contraction of the pharyngeal muscles a peristaltic wave began to traverse the oesophagus. This wave did not stop at the point of excision, but in due time reappeared below and carried the ball to the stomach. Thus the act was shown to be controlled by the central nervous system. Peristalsis was so plainly the motive power that the action was never doubted. Yet this belief was soon to be questioned. In 1880, Falk and Kronecker3 studied the movements in the mouth and pharynx, and advanced the theory that deglutition was accomplished by the rapid contraction of the muscles of the mouth. During the act of swallowing the air-tight buccal cavity shows a manometric pressure of 20 centimetres of water. The same pressure was demonstrated to be present also in the oesophagus, but not in 1 Magendie: Precis elementaire cle physiologie. Paris, 1836, i, p. 63. 2 Mosso: Moleschott’s Untersuchungen, 1876, xi, p. 331.