PEPTONISED FOOD. 345 



the chorda they dilate, and the venous blood is bright red thus, 

 it is probable that a similar nervous mechanism exists, [but as yet no 

 such mechanism has been discovered.] The secretion is excreted at 

 a pressure of more than 17 mm. Hg. (rabbit). 



Effect of nerves upon the secretion. The nerves arise from the 

 hepatic, splenic, and superior mesenteric plexuses, together with branches 

 from the vagus and sympathetic. The secretion is excited by stimula- 

 tion of the medulla oblongata (Heidenhain and Landau), as well as 

 by direct stimulation of the gland itself by induction shocks (Kuhne 

 and Lea). The secretion is suppressed by atropin, by producing vomit- 

 ing (Cl. Bernard), by stimulation of the central end of the vagus (C. 

 Ludwig and Bernstein), as well as by stimulation of other sensory 

 nerves e.g., the crural and sciatic (Afanassiew and Pawlow). Extir- 

 pation of the nerves accompanying the blood-vessels prevents the 

 above-named stimuli from acting. Lender these circumstances a thin 

 "paralytic secretion " with feeble digestive powers is formed, but its 

 amount is not influenced by the taking of food (Bernstein). 



Extirpation of the gland may be performed (Schiff), or the duct ligatured in 

 animals (Frerichs), without causing any very great change in their nutrition; the 

 absorption of fat from the intestine does not cease. After the duct is ligatured it 

 may be again restored. Ligature of the duct may cause the formation of cysts in 

 the duct and atrophy of the gland-substance. Pigeons soon die after this opera- 

 tion (Langendorff). 



172. Preparation of Peptonised Food. 



[Peptonised food may be given to patients whose digestion is feeble. 

 Dr. Wm. Roberts, of Manchester, uses various forms of this food. Food 

 may be peptonised either by peptic or tryptic digestion, but the former 

 is not so suitable as the latter, because in peptic digestion the grateful 

 odour and taste of the food are destroyed, while bitter by-products 

 are formed. Hence, Dr. Roberts employs pancreatic digestion, which 

 yields a more palatable and agreeable product. As trypsin is destroyed 

 by gastric digestion, obviously it is useless to give extract of the pan- 

 creas to a patient along with his food. 



Peptonised Milk. "A pint of milk is diluted with a quarter of a pint 

 of water and heated to 60 C. Two or three tea-spoonfuls of Benger's 

 liquor pancreaticus. together with 10 or 20 grains of bicarbonate of 

 soda, are then mixed therewith." Keep the mixture at 38 C. for about 

 two hours, and then boil it for two or three minutes, which arrests the 

 ferment action. 



Peptonised Gruel, prepared from oatmeal, or any farinaceous food, 

 is more agreeable than peptonised milk, as the bitter flavour does not 

 appear to be developed in the pancreatic digestion of vegetable proteids. 



