PANCREATIC JUICE. 339 



the juice was obtained shows generally that it was not nor- 

 mal. There is no doubt, however, that the fluid which was 

 obtained from the dog and analyzed by Bernard possessed all 

 the characteristic physiological properties. 



The chemical properties of the organic principle of the 

 pancreatic juice are distinctive. Though, like albumen, it is 

 coagulated by heat, the strong mineral acids, and absolute 

 alcohol, it differs from albumen in the fact that its dried al- 

 coholic precipitate can be redissolved in water, giving to the 

 solution all the physiological properties of the normal pan- 

 creatic secretion. Bernard has also found that pancreatine is 

 coagulated by an excess of sulphate of magnesia, which will 

 coagulate caseine but has no effect upon albumen. It is im- 

 portant to recognize this distinction between pancreatine and 

 other nitrogenized principles, especially albumen, from the 

 fact that the last-named substance has the property of forming 

 an emulsion with fats, though not so readily and completely 

 as the pancreatic juice ; and it is essential to decide whether 

 the organic principle is a peculiar and distinct substance, or 

 albumen transuded, pathologically perhaps, from the blood. 

 There can be no doubt, in view of the marked chemical and 

 physiological peculiarities of pancreatine, that this is a dis- 

 tinct proximate principle, characteristic of the pancreatic 

 secretion and found in no other fluid, 



Researches have likewise shown that pancreatine is the 

 essential physiological constituent of the pancreatic juice, 

 and the only one which gives this fluid its peculiar digestive 

 properties. The contents of the duodenum, as the partly 

 digested matters pass from the stomach, are generally acid ; 

 but this does not at all interfere with the action of the pan- 

 creatic juice. Though the secretion itself is alkaline, it re- 

 tains its physiological properties when it has been rendered 

 acid by admixture with gastric juice. 1 



The inorganic constituents of the pancreatic juice do not 

 possess any great physiological interest, inasmuch as they do 



1 BERNARD, Memoire sur le Pancreas, Paris, 1856, p. 67. 



