PANCREATIC JUICE. 337 



Some of the most interesting facts developed by Bernard 

 concerning the pancreatic juice relate to phenomena con- 

 nected with its secretion. It is important to remember that 

 the secretion of the pancreas is entirely suspended during 

 the intervals of digestion. This fact has been definitely 

 settled by Bernard, 1 and can easily be observed by opening 

 animals in digestion and while fasting. In the first instance 

 the pancreatic duct will be found full of normal secretion, 

 and in the other, it will be almost, if not entirely, empty. 

 Bernard has also found that the pancreatic juice begins to 

 flow into the duodenum during the first periods of stomach- 

 digestion, before alimentary matters have begun to pass in 

 quantity into the intestine. 



Another important fact determined by Bernard is that 

 the secretion of the pancreas is readily modified by irritation 

 and inflammation following the operation. When we come 

 to treat of the general properties of the normal pancreatic 

 fluid, it will be seen that its characteristics are, decided 

 alkalinity, viscid consistence, and coagulability by heat. It 

 is almost always the case that a few hours after the canula 

 is fixed in the duct, the juice loses some of these characters 

 and flows in abnormal quantity. "With respect to suscepti- 

 bility to irritation, the pancreas is peculiar ; and its secretion 

 is sometimes abnormal from the first moments of the experi- 

 ment, especially if the operative procedure has been pro- 

 longed and difficult. That the properties above given are 

 characteristic of the normal pancreatic secretion, there can 

 be no doubt ; as in all instances, fluid taken from the pan- 

 creatic duct of an animal suddenly killed while in full di- 

 gestion is strongly alkaline, viscid, and coagulable by heat. 

 This excessive sensitiveness of the pancreas has rendered 

 fruitless all the attempts of Bernard to establish a permanent 

 pancreatic fistula from which the normal juice could be 

 collected. 2 



1 Op. tit., p. 43. 



2 A number of physiologists have attempted to establish a permanent com- 



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