GASTRIC JUICE. 463 



may be digested by the " psychical " secretion, and then perhaps cause 

 a chemical secretion by their decomposition products. 



The secretion in the stomach may also be influenced by the small 

 intestine, and in this way, as shown by the investigations of PAWLOW 

 and his pupils, the fats have a retarding action upon the secretion of 

 juice and upon digestion by acting reflexly upon the duodenal mucosa. 

 In dogs on feeding fat (oil) with food containing starch, the secretion of 

 gastric juice remains reduced during the entire period of feeding, and 

 fat in connection with protein food has a similar action, with the excep- 

 tion that in this case the retarding action is observed only in the first 

 hours of digestion. According to PIONTKOWSKI l the oil-soaps differ from 

 the neutral fats by having a strong action on the flow of juice, and this 

 is the reason why about five to six hours after a meal with fat the secre- 

 tion of juice is stopped, as just at this time the soaps are being formed. 

 According to FROUIN the food in the intestine produces a secretion of 

 gastric juice which continues after the action of the psychic moment 

 has ceased. LECO^CB- 2 - arrived at similar results, and he ascribes a less 

 subordinate importance to the chemical secretion as compared with the 

 psychic secretion, than PAWLOW does. 



The behavior of the different parts of the stomach in secretion is 

 also of interest. The work of PAWLOW and his pupils GROSS and 

 KRSHYSCHKOWSKY, has shown that meat and its extractives as well as 

 the digestion products and milk especially act upon the pyloric part, 

 although not entirely, while they are inactive upon the fundus. Alcohol 

 also acts upon the fundus part. PopiELSKi 3 found that meat extracts 

 had an exciting action upon the secretion of gastric juice, even when intro- 

 duced subcutaneously. In close relation to what has been said above 

 stands the observation of EDKINS that the pylorus part of the stomach 

 contains a substance, a prosecretin, which by acids and certain other 

 substances is transformed into a secretin, which when introduced into 

 the blood circulation causes a secretion of gastric juice. HEMMETER, 

 claims that a secretin for the secretion of gastric juice is also produced 

 in the salivary glands. The extirpation of all the salivary glands in 

 dogs causes a marked diminution in the secretion of gastric juice, while 

 the intravenous or peritioneal injection of an extract of the salivary 

 glands of dogs produces a secretion of gastric juice. EMSMANN 4 has 

 also obtained bodies having a similar action, from the mucosa of the 



1 See Biochem. Centralbl., 3, 660. 



2 Frouin, Compt. rend. soc. biol., 53; Leconte, La Cellule, 17. 



3 Gross, Bioch. Centralbl., 5, 669; Krshyschkowsky, Maly's Jahresb., 36, 403; 

 Popielski, ibid., 39. 



4 Edkins, Journ. of Physiol., 34; Hemmeter, Bioch. Zeitschr., 11; Emsmann, 

 Intern. Beitr. zu. Path. u. Ther. d. Ernahrungs storungen 3 (1911). 



