106 LECTURE VI. 



in the second thir.d of the cells; other investigators 1 have noted globules 

 in the basal edge. The results do not enable us to arrive at any decision. 

 It has also been stated that an active ingestion of unchanged fat globules 

 takes place. 2 The epithelial cells are supposed to send out protoplasmic 

 processes which surround and absorb the fat globules. The leucocytes 

 have also been credited with a direct activity in the assimilation of the 

 fats. They are believed to migrate in the intestinal lumens and saturate 

 themselves with fat. Finally, there exists the possibility that other 

 methods may exist for fat assimilation. Aside from the fat absorption by 

 the cells, there remains the possibility of intercellular absorption. 



For the time being, we can only state with certainty that fat is emulsified 

 in the intestines, and that there is always a decomposition of fat into 

 glycerol and fatty acids. The only question is as regards the amount of 

 fat saponified. Undoubtedly the decomposed fat is recombined in the 

 walls of the intestine, so that only neutral fats are introduced into the 

 organism. 



Many factors participate in the process of fat absorption. One of the 

 most important is the pancreas. It furnishes, on the one hand, the alka- 

 line fluid which is so necessary for the emulsification of the fats, and, 

 again, it supplies the fat-splitting ferment, which produces the saponifica- 

 tion. If the amounts of the pancreatic juice be diminished, either by 

 extirpation of the gland, or through ligating the ducts of the pancreas, an 

 appreciable reduction in fat absorption takes place. It is not entirely 

 abolished, for Abelmann 3 has shown an absorption of 28-53 per cent of 

 milk-fat under these conditions. Sandmeyer has shown that, if dogs 

 whose pancreatic glands have been removed are fed with finely chopped 

 pancreas, the amount of fat absorbed can be increased. 



It is still a question whether the absence of lipase, which results 

 on the removal of the pancreatic juice, is the cause of the diminished 

 fat assimilation. If it be true that a copious emulsification is sufficient to 

 cause a fat absorption, we must conclude that this can take place without 

 the pancreatic lipase being necessarily present, because fatty acids are 

 certainly set free in the stomach, and fats can also be decomposed by 

 bacterial action. The formation of an emulsion might, on the other hand, 

 tend to prevent the diminution in amount of the alkaline pancreatic juice. 

 If we saturate an emulsion of fat with an acid, we observe that the emulsion 



1 Cf. I. Munk: Zentr. Physiol. 14, 6/7, 121, 152, 409 (1900). Heidenhain: Pfluger's 

 Arch. 43, Sup. 85 (1888). Kischensky: Zentr. allg. Path. u. path. Anat. Heft 1, 

 1902; Beitrage z. path. Anat. u. z. allg. Path. 32 (1902). 



2 Cf. Zawarykin: Pfluger's Arch. 31, 231 (1883). Heidenhain: loc. cit. L. V. 

 Thanhoffer: ibid. 8, 391 (1874). R. Wiedersheim : Festsch. 56 Versam. deut. Natur- 

 fors. Aerzte, 1883. 



3 Abelmann: Inaug. Diss. Dorpat, 1890. Cf. W. Sandmeyer: Z. Biol. 31, 12 (1894), 



