Relations between hydrochloric acid secretion and electrical phenomena in frog gastric mucosa

For over a huindred years the existence ofa potential difference (p.d.) across the stomach wall has been recognized, and there has been sporadic speculation as to the relation, if any, between this p.d. and the secretory activity of the gastric mucosa. The p.d. was first recorded by Donn6 (1834) who, discussing these 'courants 6lectriques' asked 'sont-ils capables de rapprocher, de separer les molecules l'une de l'autre, et de donner naissa,nce A des corps nouveaux, comme cela arrive dans le regne inorganique?' This question still remains unanswered in spite of a large amount of work by numerous investigators. The early experiments, using primitive techniques and uncontrolled conditions, have been reviewed by Biedermann (1895). Later work, some with more refined techniques, but still using the stomach in 8itu, have been discussed by Rehm (1944) and by In the present investigations isolated frog gastric mucosa was chosen as the experimental material because it can secrete hydrochloric acid in vitro, under conditions capable of controlled variations, and because it is possible to obtain in- formation about its metabolic activity (Davies, Longmuir & Crane, 1947). These investigations into a possible correlation between electric properties and metabolism were initiated in 1945, 'after it had become clear that the hydrogen ions of the acid could not be produced directly by-the fermentation or oxidative degradation of any carbon compound (Davies, 1948; Davies et al. 1947).