136 THE DIGESTIVE FLUIDS. 



Human. Human. 



(Herter's case.) (Zawiidsky's case.) 



Water 975.9 864.05 



Solids 24.2 135.95 



Peptones and enzymes ) 1 , _ 



(no albumin) / n - 5 92.05 



Alcoholic extract 6.4 43.90 



Mineral ash 6.2 3.44 



ANALYSIS OF THE CONTENTS OF A PANCREATIC CYST (LENARCIC), 



Water ..." 928.1 



Solids 17.9 



Organic matter 10.05 



Mineral ash 7.85 



The Ferments and their Zymogens. 



The most important constituents of the pancreatic juice are the 

 ferments, of which five different forms are said to be present. 

 These are trypsin, steapsin, an amylolytic ferment (which is said 

 to be identical with the salivary ptyalin), maltase, and chymosin. 

 Like the ferments which are furnished by the salivary glands and 

 the central cells of the gastric glands, these enzymes occur also in the 

 pancreatic cells in the form of zymogens, which are subsequently 

 transformed into the active ferments. If a fresh pancreas is thus 

 extracted with glycerin, it will be noted that the resulting extract 

 has no proteolytic properties whatever, while an extract obtained 

 after the gland has been hashed and exposed to the air for some 

 time, or an aqueous extract of the fresh gland, digests albumins 

 with ease. If the fresh gland, further, is hashed and briefly treated 

 with a 1 per cent, solution of acetic acid, and then extracted with 

 glycerin, an active preparation is obtained at once. Similar results 

 are reached in the case of the pancreatic ptyalin. If a fresh pancreas 

 is thus repeatedly extracted with glycerin until ptyalin no longer 

 passes into solution, and the gland is then washed in water and left 

 exposed to the air for a short time, an additional amount of the 

 ferment can be obtained by further extraction with the same reagent. 

 In what manner the transformation of trypsinogen, ptyalinogen, 

 steapsinogen, and the other zymogens, into, the corresponding fer- 

 ments is normally effected, is unknown. But, as has been seen, this 

 can be brought about artificially through the influence of water, 

 dilute acetic acid, and probably also through the activity of acid- 

 forming bacteria or the oxygen of the air. 



Of the chemical composition of the /yn logons we know little, but 

 it appears that they are of an albuminous nature and of a more 

 complex composition than the ferments themselves. On decomposi- 

 tion trypsinogen thus yields the corresponding ferment and an 

 unknown albuminous substance. Of the origin of the zymogens, 

 and of the manner in which they are produced in the cells, we know 7 

 nothing. 



Trypsin. Trypsin is the most important proteolytic ferment 



