Preliminary note on the origin of the hydrochloric acid in the gastric tubules

Abstract

The place of origin in the peptic glands of the hydrochloric acid of the gastric juice has been, during the last 60 years, a question the solution of which has been directly attempted by a number of observers whose efforts have on the whole been unsuccessful. The first to attack the question was Claude Bernard, who sought to localise the acid formation in the glands by injecting into the blood-vessels of a rabbit, first a solution of lactate of iron and thereafter one of potassium ferrocyanide. When the two solutions mingle in the circulating fluid and tissues of the body the mixture should, he assumed, only give the Prussian blue reaction in the presence of a free acid, and, in consequence, when diffused through the gastric glands, it should develop the blue reaction where the hydrochloric acid is formed. The assumption is not quite correct. The mixture of the two solutions, as soon as it is made, in the test-tube, develops Prussian blue when the purest reagents are employed and, therefore, though the addition of an acid greatly enhances the blue reaction, the latter is not infallible evidence of the occurrence of a free acid. With this method, however, Bernard found a blue deposit on the surface of the mucosa in the lesser curvature of the stomach, but no trace of blue in the interior of the mucosa. This result left the question undecided.