478 DIGESTION. 



Amylopsin or pancreatic diastase, which, according to KOROWIN 

 and ZWEIFEL, is not found in new-born infants and does not appear 

 until more than one month after birth, seems, although "not identical 

 with ptyalin, to be closely related to it. Amylopsin acts very energetically 

 upon boiled starch, and according to KUHNE also upon unboiled starch, 

 especially at 37 to 40 C., and according to VERNON l best at 35 C. It 

 forms, similarly to the action of saliva, besides dextrin, chiefly isomaltose 

 and maltose, with only very little dextrose (MUSCULUS and v. MERING, 

 KULZ and VoGEL 2 ). The dextrose is probably formed by the action 

 of the invertin existing in the gland and juice. The pancreatic juice 

 of the dog in fact, contains, according to BIERRY and TERRoiNE, 3 maltase, 

 its action becomes apparent only after very faint acidification of the 

 juice. According to RACHFORD the action of the amylopsin is not reduced 

 by very small quantities of hydrochloric acid, but is diminished by larger 

 amounts. VERNON, GRUTZNER, and WACHSMANN 4 find that the action 

 is indeed accelerated by very small quantities of hydrochloric acid, 0.045 

 p. m. while alkalies in very small amounts have a retarding action. 

 This retarding action of alkalies and hydrochloric acid may be stopped 

 by bile (RACHFORD.) 



Steapsin or Fat-splitting Enzyme. The action of the pancreatic 

 juice on fats is twofold. First, the neutral fats are split into fatty acids 

 and glycerin, which is an enzymotic process; and secondly, it has also 

 the property of emulsifying the fats. 



The action of the pancreatic juice in splitting the fats may be shown 

 in the following way: Shake olive-oil with caustic soda and ether, 

 siphon off the ether and filter if necessary, then shake the ether repeatedly 

 with water and evaporate at a gentle heat. In this way is obtained a 

 residue of fat free from fatty acids, which is neutral and which dissolves 

 in acid-free alcohol and is not colored red by alkanet tincture. If such 

 fat is mixed with perfectly fresh alkaline pancreatic j uice or with a freshly 

 prepared infusion of the fresh gland and treated with a little alkali or 

 with a faintly alkaline glycerin extract of the fresh gland (9 parts gly- 

 cerin and 1 part 1 per cent soda solution for each gram of the gland), 

 and some litmus tincture added and the mixture warmed to 37 C., 

 the alkaline reaction will gradually disappear and an acid one take its 

 place. This acid reaction depends upon the conversion of the neutral 

 fats by the enzyme into glycerin and free fatty acids. A very much 

 used method consists in determining the acidity of the mixture by means 

 of titration before and after the action of the juice or the infusion. 



1 Korowin, Maly's Jahresber., 3; Zweifel, footnote 3, p. 431; Kiihne, Lehrbuch, 

 117; Vernon, Journ. of Physiol., 27. 



2 See footnote 1, p. 432. 



3 See Tebb, Journ. -;f Physiol., 15; Bierry and Terroine, Compt. rend. soc. biolog., 

 58; Bierry, ibid., 62. 



4 Rachfcrd, Amer. Journ. of Physiol., 2; Vernon, 1, c.; Griitzner, Pfliiger's 

 Arch., 91. 



