70 PROTEIN DIGESTION IN THE INTESTINE 



In another series of experiments 60 Abderhalden fed gela- 

 tin which is not a full equivalent for protein because the ani- 

 mal cells are apparently unable to form de novo certain build- 

 ing stones which are absent from gelatin. He then sought 

 to increase the chance of protein synthesis in the organism 

 during a full diet of carbohydrates and fats by adding am- 

 monium acetate to the gelatin. But the nitrogen record 

 constantly remained negative. "From these experimental 

 results we may conclude, " he says, "that the basis for 

 protein synthesis is not to be found in ammonium salts with 

 carbohydrate or fatty material. ' ' 



London's Studies. It is impossible to conclude the sub- 

 ject of protein digestion in the intestine without special con- 

 sideration of the investigations which for years E. S. London 

 with a number of collaborators has been conducting in the In- 

 stitute of Experimental Medicine in St. Petersburg. London 

 has developed the technic of intestinal fistulas to a high de- 

 gree of perfection. He is not satisfied to provide a single 

 fistula in the experimental animal ; his "polyfistulous dogs" 

 enable him to make comparative studies of various intestinal 

 levels at one given time ; his ' * panchymotic dog, ' ' wearing in 

 addition to a double-chambered duodenal canula a gastric 

 and a jejunal canula, puts him in position to obtain coinci- 

 dently the gastric secretion, the bile, the pancreatic juice and 

 the intestinal secretion in proper isolation from each other. 



For a number of years London has been publishing the 

 results of his studies in a very long series of contributions 

 embracing a wealth of individual observations. 61 They 

 take up the rate of protein catabolism, the resorption inten- 

 sity and movement of the intestinal contents in particular 



60 E. Abderhalden and A. E. Lampe", Zeitschr. f. physiol. Chem., 80, 

 160, 1912. 



61 E. S. London and associates, numerous publications in the last thirty 

 volumes of Zeitschr. f. physiol. Chem. 



