ON PANCREATIC PROTEOLYSIS. 195 



of this question, for the results which the paper presents are 

 so at variance with the above conclusions and so out of 

 harmony with generally accepted views, that some explanation 

 of the apparent divergence must be sought. This is all the 

 more necessary from the fact that comparatively few systematic 

 quantitative experiments have been tried. We have, therefore, 

 attempted a thorough study of the subject with a view to 

 establishing firmly the nature and extent of the action which 

 bile and its constituents exercise upon pancreatic proteolysis. 



In the experiments reported by Rachford and Southgate 

 emphasis is laid upon the fact that they were " planned for the 

 purpose of throwing some light on the proteolytic action of 

 pancreatic juice, under the conditions which normally exist hi 

 the duodenum." With this end in view pure pancreatic juice 

 was obtained from rabbits, through a pancreatic fistula, one 

 rabbit yielding about 1 c.c. of the secretion in from four to six 

 hours, this quantity sufficing for one experiment. As to the 

 character of the bile employed there is no mention. We call 

 attention to these facts because there is a manifest disposition 

 on the part of these writers to accept the results of other 

 workers in this field as conclusive for the pancreatic extracts, 

 etc., employed, while their own divergent results are to be 

 accepted as equally conclusive for the natural pancreatic juice. 

 We are disinclined, however, to admit the correctness of this 

 view. Pancreatic juice owes its proteolytic power to a specific 

 enzyme. If the digestive power of this secretion is modified 

 by the presence of bile through a specific action upon the 

 enzyme, it is clear that this influence will be exerted whether 

 we are dealing with the natural secretion or with an extract of 

 the gland. If, however, the influence exerted is an indirect 

 one, affecting the enzyme only through changes of reaction, 

 etc., it is equally manifest that this influence can be detected 

 and measured to the best advantage when the environment is 

 thoroughly known. We see, therefore, no particular advantage 

 in making use of the natural secretion in a study of this kind, 

 especially where the volume available is so small as to render 

 the attainment of accurate quantitative results somewhat 



