CHAPTER XV 

 DIGESTION AND RESORPTION OF FATS 



HEREWITH we turn our steps to a new field, that of the 

 biochemistry of fats. It will undoubtedly be found best to 

 continue very much in the same way as in the discussion of 

 protein and carbohydrate metabolism, beginning with the 

 introduction of the fats into the digestive tract, then dealing 

 with their digestion and resorption, thereafter following 

 them on their way through the chyle- and lymph-paths and 

 through the tissues, up to where they and their cleavage 

 products begin to sink into the depths of the intermediate 

 metabolism and pass out of sight. 



The Lipase of the Stomach. Beginning then with consid- 

 eration of the process of fat digestion, the first phase to be 

 considered is the gastric digestion of fats. 1 It is true there 

 has been much written upon this subject, but really there is 

 very little that can be said about it. Doubtless, according to 

 the investigations of Volhard and others, the stomach con- 

 tains a lipolytic ferment and physiologically the splitting of 

 fat begins at this point. Thus London 2 found in a dog with 

 gastric fistula that about one-third of the fat introduced in 

 emulsified form was split in the stomach into glycerol and 

 fatty acids. There is probably no doubt, too, that at times 

 some fat is resorbed in the stomach. Otto Weiss 3 observed 

 a resorption process of this sort in the stomach of ringed 

 snakes and in the stomachs of newborn dogs and cats; in 

 adult human beings, however, it is unquestionably insigni- 

 ficant. Apparently, too, the lipolytic power of pure gastric 



literature upon Gastric Lipase: C. Oppenheimer, Die Fermente, 3d ed., 

 11, pp. 15-16, 1909. 



a E. S. London and M. A. Wersilowa, Zeitschr. f. physiol. Chem., 56, 545, 

 1908. 



8 O. Weiss (Physiol. Instit., Konigsberg) , Pfliiger's Arch., 144, 540, 1912; 

 cf. also W. Lamb. Jour, of Physiol., 40, Proc. Physiol. Soc., xxiii, 1910 (Fat 

 Resorption in the Stomach of Kittens). 

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