EFFECTS ON THE ALIMENTARY CANAL 321 



Grunhagen and Krohn ('89) noted that during hibernation the intestinal 

 epithelium of frogs may serve as a storehouse of fat, which occurs in groups of 

 cells between the villi. Nicolas ('90) and Krehl ('90) described in detail the 

 changes in the intestinal epithelium during fat absorption. 



Mingazzini ('00, '00a) claimed that in fasting fowls the surface epithelial 

 cells of the villi, which are 40/i high during digestion and absorption of food, are 

 soon reduced to half this height by the disintegration and resorption of the basal 

 ends of the cells, giving rise to subepithelial spaces. This phenomenon was 

 considered a part of the normal process of digestion and resorption. This 

 theory was confirmed to a certain extent by Reuter ('03) for the rat and mouse 

 and by Pugliese ('05) in dogs; but it was opposed by Beguin ('04) for Lacerta 

 and Bnfo; by Bezzola ('04) for fowls and other animals; by Luca ('05) for the 

 chick, cat, rat, guinea pig and bat; by Arcangeli for Box salpa; by Corti ('06) 

 for the hibernating hedgehog {Erinaceus europaeus); by Biscossi ('08) for the 

 sparrow; and by Demjanenko ('09) in numerous species. The spaces of 

 Mingazzini have usually been interpreted by subsequent investigators as arte- 

 facts due to shrinkage or imperfect fixation. 



Luca ('05a) described in the fowl's intestine a subepithelial layer of mast 

 cells, which become atrophic during starvation 3-8 days, with deeply staining 

 granules obscuring the poorly stained nuclei. 



Asher ('08) by Altmann's method found the granules in the epithelial cells 

 of the villi larger and more numerous in rats starved 2 days (water only) than 

 in those normally fed. In the glands of Lieberkiihn, however, the granules 

 appeared smaller and indistinct during inanition. Champy ('09) described 

 the mitochondria in the intestinal epithelium of fasting animals (triton, turtle, 

 axolotl, frog, lizard, snake, rat, Myoxus, and guinea pig), and claimed that they 

 are transformed from filaments into granules during digestion and absorption. 

 The changes especially in the granules and mitochondria of the epithelial cells 

 during digestion, absorption and the early stages of fasting have also been 

 described by Demjanenko ('09) in fishes, amphibia, pigeon, rat, guinea pig, cat 

 and dog; and by Zillenberg-Paul ('09) and Holthusen ('10) in various species; 

 by Policard ('10) in the frog {Rana temp or arid); by Stickel ('10) in the human 

 newborn, also starved puppies; by Corti ('12) in fishes, Lacerta, Gallus, Mus 

 decumanus, Vesperugo, and in Erinaceus and Vesperugo during hibernation. 

 The literature on the question of the significance of the various granules in the 

 intestinal epithelium and their changes during digestion, absorption and 

 the early stages of inanition has been reviewed fully by Arnold ('14). 



Mcintosh ('18) noted fat droplets in the epithelium of the mucosa and 

 associated glands in the stomach and intestine of cats fasting 24-48 hours. 

 He concluded that these lipoidal granules are probably normally present, 

 independent of fat absorption. Tang ('22) used varied technique in studying 

 the Paneth cells in several mammals during fasting, including the squirrel (to 

 no hours), guinea pig (to 170 hours) and the pig (starved 10 days). There is 

 apparently at first a shrinkage in size of the Paneth cells, with a variable increase 

 later. The cell structures show certain changes, but the secretory granules are 

 retained and there is no indication of degeneration. " 



