270 



DIGESTION 



Proteid 



FIG. 106. The course of pancreatic secretion in man, 

 after a meal consisting of soup, meat, and rolls, after 

 Glaessner. 



Hours 12345 1 



one) be introduced into the 

 duodenum, after a short 

 latent period, a copious se- 

 cretion of pancreatic juice 

 is poured out. The acid 

 gastric juice flowing through 

 the pylorus obviously must 

 have exactly the same effect 

 ( Gottlieb, Pawlow ) . As soon 

 as the pyloric sphincter opens 

 and gastric juice pours out 

 into the small intestine, the 

 conditions are present for an 

 abundant flow of pancreatic 

 juice. 



This influence of acids is 

 beautifully confirmed by the 

 fact that a flow of pancreatic 

 juice caused by the gastric secretion is reduced considerably when the stomach 

 contents are neutralized by administration of alkaline fluids. 



Since the vagus causes the flow of gastric juice also, it might be thought 

 that the secretion of the pan- 

 creas under the influence of 

 this nerve begins only under 

 the stimulating action of the 

 acid gastric juice. But this 

 is not true, for on artificial 

 stimulation of the vagus the 

 pancreas begins to secrete 

 sooner than the stomach, and 

 besides, the pancreatic secre- 

 tion makes its appearance 

 even if the pylorus be firm- 

 ly ligated so as to prevent 

 any passage of gastric juice 

 (Popielski). 



Water and neutral fats 

 in the intestine are men- 

 tioned by Pawlow as special 

 excitants of the pancreatic 

 secretion (in man adminis- 

 tration of fat was without 

 effect) ; other authors have 

 succeeded in inducing a se- 

 cretion by means of mus- 

 tard, pepper, chloral hy- 

 drate, ether, etc. 



Formerly it was supposed Meat Bread Milk 



that this secretion is in the FJG lf)7 _ The course of secr etion in the pancreas of the 

 nature of a reflex and is dog> after f ee dirig exclusively with meat, with bread 



mediated by the afferent and with milk, after Walther. 



