PANCREATIC DIGESTION. 



The composition and character of pancreatic juice varies 

 greatly under different conditions. Thus far it has been 

 practically impossible to collect the juice in a manner which 

 will permit of the assumption that it is comparable to that 

 secreted into the intestine. 



The juice as obtained from a temporary fistula is clear, 

 viscous, and alkaline in reaction, the alkalinity corresponding 

 to about a 0.5 per cent Na 2 C0 3 solution. It differs from 

 the gastric juice hi being rich in proteins, having a sp. gr. 

 of about 1.030. The character and quantity of the enzymes 

 which may be present hi the fluid varies considerably accord - 

 ing to the nature of the diet. 



The following have been shown to exist in different 

 extracts of the gland and in the secretion itself at certain 

 times. 



1. Trypsin a proteolytic enzyme appearing first in the 

 gland as a zymogen, trypsinogen, entirely comparable to 

 pepsinogen. 



2..Amylopsin or pancreatic diastase an amylolytic en- 

 zyme almost identical with ptyalin. 



3. Steapsin or lipase a lipolytic enzyme probably not 

 characteristic of the pancreatic juice. 



4. Pancreatic rennin a coagulating enzyme acting on 

 the caseinogen of milk in a way somewhat similar to the 

 gastric rennin. Various extracts of the pancreatic gland 



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