ON PANCREATIC PROTEOLYSIS. 



219 



filtrate were readily soluble in water, but the alcoholic pre- 

 cipitate was not completely soluble. Following are the re- 

 sults obtained: 



Experiment 42. With a neutral extract of ox pancreas. 



Per cent of Bile Constituents. 



Undigested 

 Residue. 



Fibrin 

 Digested. 



0.4217 gram 



0.50 Bile salts .... 0.4633 



1.00 .... 0.4452 



1.50 " .... 0.4415 



0.25 Alcoholic p.p. . . . 0.3862 



0.50 "... 0.3704 



1.00 " "... 0.4059 



0.50 Alcohol-ether filtrate 0.4147 



1.00 " " 0.4032 



1.50 " " 0.3759 



Relative 



Prot eolyt ic Action. 



57.83 per cent 100.0 



54.67 94.5 

 55.48 95.9 

 55.85 96.5 

 61.38 106.1 

 62.96 108.8 

 59.41 102.7 

 58.53 101.2 



59.68 103.2 

 62.41 107.9 



Experiment 43. A duplicate of the preceding, except that an alkaline (0.25 

 per cent Na 2 C0 8 ) extract of ox pancreas was employed. 



Fibrin Relative 



Mgested. Proteolytic Action. 



81.14 per cent 100.0 



71.53 88.1 



71.17 87.7 



73.45 90.5 



76.12 98.8 



76.55 94.3 



76.30 94.0 



75.27 92.7 



70.71 87.1 



73.11 90.1 



From the first of these two experiments, where a neutral 

 pancreatic fluid was employed, it is seen that the fraction con- 

 taining the bile salts produces a slight inhibition of proteolysis, 

 while the other two fractions increase the proteolytic action of 

 the enzyme. Also noticeable is the tendency of the material 

 from the alcohol-ether filtrate to increase proteolysis in pro- 

 portion to the amount added, while the favorable action of the 

 alcoholic precipitate appears to diminish with increase in the 

 proportion used. That these peculiarities of action, however, 

 are not due to any direct influence upon the proteolytic 

 enzyme is evident from the fact that in the second experiment 

 where the reaction of the digestive mixtures is alkaline these 



