( 255 ) 



too enters the agar. It is by mixing with HC1 converted into pepsin 

 and so determined quantitatively with the pepsin. 



2. Distribution of pepsinogen. 



As has been said, the investigations of Langley ! ) have shown 

 that, contrary to pepsin, pepsinogen is not destroyed by a solution 

 of jS r a 2 CO s 0.3%. We have made use of this fact to try if we could 

 withdraw pepsinogen from the mucous membrane. 



For tli is purpose agar columns were placed upon the mucous 

 membrane containing 2% of agar in a Na,CO, solution of 0.3%. 

 The column again had a diameter of 22 mM., the contents being 3 cc. 



It must be casually observed that separate experiments had shown 

 that in such an alkalic agar mass, pepsin at once loses irretrievably 

 its digestive power. 



To the method of experimenting we have not much to add. Let 

 us only mention that the alkalic agar, after having been in contact 

 with the mucous membrane was cut fine, neutralized with diluted 

 hydrochloric acid, then mixed with 3 cc. HC1 of 0.4%- The purpose 

 of this was, to liberate the pepsin from the pepsinogen. The digesting- 

 experiments with albumen-tubes gave the results tabulated below. 

 Here the lengths of the 4 digested albumen columns have each time 

 been added together. 



TABLE III. 



The agar columns were kept on the mucous membrane for 20 hours. 



It will be seen that from the cardea part (A and A') no pepsinogen 

 zoas extracted. This need not surprise us ; for in several experiments 

 with neutral agar, no pepsin could be extracted from it either. 



In the border region between cardea and fundus, pepsinogen 

 loas found, but in a small quantity. It loas considerable in the 

 fundus (C), gradually growing less towards the pylorus (D and E). 



1 ) Langley, 1. c 



