EFFECT OF VAGOTOMY ON THE GASTRIC SECRETORY AREA IN DOGS

Abstract

Direct visualization of the gastric acid secretion as well as pH determination were carried out under several vagal preparations accompanied by maximum histamine stimulation.Under Nembutal anesthesia, canine stomach was opened along the greater curvature and the entire gastric mucosa was exposed for the direct observation of the gastric acid secretion which was possible by applying Congo red-Carbowax on the gastric mucosa.The results obtained are summarized as follows:1. Unilateral vagotomy at the height of the neck resulted in the decrease in the acid secretory areas on both anterior and posterior walls of the stomach, which was later enhanced by bilateral vagotomy. Vagotomy also decreased an acidity of the gastric juice.2. Severance of vagi was attempted supradiaphragmatically and subdiaphragmatically as well. Section of the anterior branch showed an inclination in the reduction of an acid secretory area mostly of the anterior wall, and section of the posterior branch resulted in vice versa. This inclination of limited and partial reduction in the acid secretory area of the gastric mucosa was more predominant in the dogs where the vagus or vagi were severed subdiaphragmatically. Section of the vagus at these levels also reduced an acidity of the gastric juice.3. Out of the results described above, it was shown that the decrease in the acid secretory area well correlated with the vagally denervated area of the gastric mucosa traced anatomically from the site of vagotmy.4. In the reduction of an acid secretory area induced by vagotomy, it was of some interest to notice that the acid secretory area tended to localize to the corpus mucosa adjacent to the antral border. Histologically, this area well coincides with the richly distributed area of the parietal cells.