324 IV. DIGESTION OF LIPIDS OTHER THAN FATS 



demonstrated that, when 11% of lard or olive oil was added to low-calcium 

 diets having a high proportion of wheat flour or bread, the rats did not 

 develop rickets. 



As in the case of carotene and vitamin A, the absorption of vitamin 

 D requires the presence of bile. It had long been recognized that, when 

 bile was excluded from the gastrointestinal tract, osteoporosis de- 

 veloped. 481-489 It was suggested by Diittmann 484 that vitamin D is not 

 absorbed in the absence of bile, and that this, in turn, leads to a negative 

 calcium and phosphorus balance. However, Seifert 490 ascribes this de- 

 ficiency to an inability to absorb vitamin A. The accuracy of the former 

 explanation is indicated by the fact that this pathological condition is 

 relieved by the parenteral administration of vitamin D. 491 Conclusive 

 proof of this hypothesis was brought forward by Greaves and Schmidt, 492 

 who studied the absorption of vitamin D in choledochocolostomized rats 

 by the use of calcium and phosphorus balances as a criterion of vitamin D 

 absorption. Bile fistula*rats were found to be in negative calcium balance, 

 and little or no irradiated ergosterol was absorbed in the gastrointestinal 

 tract. On the other hand, when desoxycholic acid was given orally, 

 irradiated ergosterol could be carried across the intestinal wall of the bile 

 fistula rat. 



Heymann 493 likewise reported that vitamin D is absent from the blood, 

 and that a hyperphosphatemic reaction does not occur in dogs whose bile 

 ducts have been ligated and transected following the administration of 

 viosterol (vitamin D 2 in oil) or drisdol (vitamin D 2 in propylene glycol) 

 by stomach tube. Vitamin D was not absorbed unless bile was present 

 in the chyme. In this case, no difference was noted in the relative effect 

 of the solvents employed. On the other hand, when these preparations 

 were given to bile-fistula dogs by intramuscular injection, a considerable 



481 I. P. Pavlov, Verh, Ges. russ. Aerzte, 72, 314 (1904-1905); cited by J. D. Greaves 

 and C. L. A. Schmidt, J. Biol. Chem., 102, 101-112 (1933), p. 101, and by G. Duttmann, 

 Beitr. klin. Chir. (Brim's), 139, 720-729 (1927). 



482 E. Looser, Verhandl. deut. path. Ges., 11, 291-295 (1907). 



483 y. P. Wiener and G. H. Whipple, Am. J. Physiol, 60, 119-133 (1922). 



484 G. Duttmann, Beitr. klin. Chir. (Brim's), 139, 720-729 (1927). 

 48 * E. Gilbert, Z. ges. exptl. Med., 43, 539-544 (1924). 



486 W. C. Buchbinder and R. Kern, Arch. Internal Med., 40, 900-910 (1927). 



487 W. C. Buchbinder and R. Kern, Am. J. Physiol, 80, 273-277 (1927). 



488 H. Seidel, Munch, yned. Wochschr., 57, 2034-2036 (1910). 



489 D. Rigano-Irrera, Cultura med. mod., 10, 43-50 (1931). 



490 E. Seifert, Beitr. klin. Chir. (Brun's), 136, 496-498 (1926). 



491 H. Tammann, Beitr. klin. Chir. (Brim's), 142, 83-120 (1928). 



492 J. D. Greaves and C. L. A. Schmidt, J. Biol Chem., 102, 101-112 (1933). 



493 W. Hevmann, ./. Biol. Chem., 122, 249-256 (1937-1938). 



