On the motor activities of the alimentary canal after splanchnic and vagus section

Abstract

In this investigation one series of animals was studied with only splanchnic nerves cut, and another series with only vagus nerves cut, and a third series with an entire severance of vagi and splanchnics. The animals used were cats.

After the observations the movements of the various parts of the alimentary canal were studied by means of the shadows cast on a fluoroscope when food mixed with bismuth subnitrate had been fed and the animals exposed to the X-rays.

Movements of the esophagus. — Splanchnic section resulted in no deviation from the normal. Bilateral vagus section resulted in the well-known paralysis of the thoracic esophagus. Swallowed food accumulated in the esophagus, and, during the first few days after operation, food was frequently regurgitated. The regurgitation, however, did not persist; there was still a hindrance to an easy passage through the esophagus, but swallowed food reached the stomach. In one case, nineteen days after the second vagus nerve had been cut, a bolus of semi-fluid material was seen moving slowly and steadily along the lower esophagus into the stomach. In one case, nineteen days after the second vagus nerve had been cut, a bolus of semi-fluid material was seen moving slowly and steadily along the lower esophagus into the stomach. Peristalsis alone could have done this. A distinction must be drawn between the immediate paralyzing effect on the esophagus of cutting the vagi, and the later partial or almost complete recovery of efficiency by a local mechanism in the lower esophageal wall.

Movements of the stomach. - Splanchnic section caused no alteration from the normal movements. The immediate effect of vagus section was tardiness in the starting of gastric peristalsis after food was introduced into the stomach. There was sometimes a delay of three or four hours, and the waves, when started, were extraordinarily shallow.