The secretion of pepsin during the gastric phase of gastric secretion.

Abstract

Summary.Special arrangements made it possible to obtain a constant secretory rate of gastric juice for many hours in Heidenhain pouch dogs, whether stimulated by histamine or food (bone‐dust and meat). It was found that the pepsin output in gastric juice secreted in response to food is not significantly different from that of gastric juice secreted in response to histamine, providing the secretory rates are comparable.In other experiments, four dogs in which a constant secretory rate was obtained by giving food, got bones and hard bread. No significant increase of the secretory rate or the output of pepsin was observed.The instillation of an extract of bone‐dust and meat into the Heidenhain pouch of three dogs did not cause an increased output of pepsin in gastric juice secreted in response to food.In experiments on anaesthetized cats, the pyloric part of the stomach was separated from the main stomach by a suture in volving the mucosa only. When a constant secretory rate of gastric juice from the main stomach was obtained by administering histamine, the extract of bone‐dust and meat was introduced into the pyloric part under pressure. In no case was there an increase of the secretory rate, nor of the output of pepsin.In five other cats the extract was introduced into the main stomach for half an hour during stimulation by histamine. The secretory rate was uninfluenced in all cases, but in two cats there was a slight increase of the output of pepsin in the first 2–3 samples obtained after the instillation.The results are discussed and it is concluded that during the gastric phase of gastric secretion there is probably no humoral or hormonal mechanism activating the pepsin producing cells. The possibility exists that these cells are stimulated directly by the food in contact with the mucosa, maybe through a reflex by the short nerve‐paths. It is suggested that the activity of the peptic cells depends on acetylcholine alone, not only during the cephalic phase but also during the gastric phase of gastric secretion.