Research into the chemical processes in the small intestine of man / by Allan Macfadyen, M.D. Ed., M. Nencki, M.D., and N. Sieber, M.D.

  • Macfayden, Allan, 1860-1907
Date:
[1891?]
Catalogue details

Licence: Public Domain Mark

Credit: Research into the chemical processes in the small intestine of man / by Allan Macfadyen, M.D. Ed., M. Nencki, M.D., and N. Sieber, M.D. Source: Wellcome Collection.

    12/44 (page 398)
    One fact is especially worthy of notice, viz., our observatio that the contents of the small intestine in its entire length ha^ an acid reaction. In animals, and in cases of fistula in th small intestine of man, this observation has repeatedly bee made. Tiedemann and Gmelin1 state that in fasting anima the fluid contained in the small intestine reddened litmti paper, and that this acid reaction diminished towards the lowe part of the intestine. The same authors confirm the fact, fire observed by Prevost and Le Royer,2 that the food-mass in th first two stomachs of ruminants has an alkaline reaction. I the third stomach the contents were thinner and reddene litmus paper, similarly also in the rennet stomach, and in th whole of the small intestine to the end of the ileum, where th acidity completely disappeared. In the Carnivora, according t Meissner, the contents of the duodenum have always an aci reaction. Ewald states that in his patient, with a fistul probably in the lower part of the small intestine, the reactio of the fresh discharge immediately tested was neutral or faintl acid, but at no time alkaline. We may mention here that th intestinal contents should first be filtered before testing th reaction or estimating the acidity. This removes the deepl bile-stained constituents of the food-mass, which tend to mas' the reaction. It often occurred that whilst the reaction of th fresh discharge seemed to us doubtful, the filtrate had a dis tinctly acid reaction. The causes of the acid reaction of th contents of the small intestine down to the caecum, are un doubtedly organic acids, and chief amongst these acetic acic The lactic acids formed in the digestive tract are neutralised b the alkali supplied by the mucosa. The neutralisation of th hydrochloric acid of the gastric juice takes place in the uppe part of the intestine. We repeatedly tested the filtered intes tinal contents with the methyl-violet and the Ginsburg reagen for free hydrochloric acid. The results were always negative. All analyses of the intestinal juice consistently show that thi secretion contains sodic carbonate, and it was interesting to not in our patient that the mucous coat of the ileum reacted alka line, the food-mass covering it acid. Incidentally we observe* 1 Berzelius’ Jahresbericht, vol. vii., 1828. 2 Berzelius’ Jahresbericht, vol. v.. 1826.