The origin of the hydrochloric acid in the gastric tubules

Abstract

In 1823 William Prout brought forward the view that the acid normally existing in the stomach was free hydrochloric acid, or to quote his own words, "free or, at least, unsaturated muriatic acid." This opinion was based on the analyses made by him of the gastric contents of the rabbit and of other animals, and of the fluid ejected from the human stomach in severe cases of dyspepsia. He said further: "With respect to the nature of this acid, very various opinions have been entertained. Some of the older chemists seem to have considered it as an acid sui generis ; by others it was supposed to be the phosphoric, the acetic, the lactic, etc. No less various have been the opinions respecting its origin and use, some supposing that it is derived from the stomach itself, and is essential to the digestive process, other that it is derived from the food, or is a result of fermentation, etc. ; in short, there seems to be no physiological subject so imperfectly understood, or concerning which there has been such a variety of opinions." These words written in retrospection by the first exponent of the free hydrochloric acid theory, when read in the twentieth century, have the significance also of a prognostication, for during the past eighty-seven years interminable discussion has ensued between the advocates of the mineral and organic acid theories respectively, and in spite of the efforts of the physiologist, biologist, and bio-chemist in their several fields, uncertainly still exists on many and similar points. This is true in particular of the structure or structures of the gastric mucosa directly concerned with the formation and secretion of the hydrochloric acid, as well as of the existence even of hydrochloric acid in a demonstrable form within the glad tubules.