LIPID STORAGE UNDER ABNORMAL CONDITIONS 675 



acts by rendering the methionine from ingested protein available for lipo- 

 tropic purposes. 



Confirmation of the mechanism of action of the pancreatic preparations 

 has been obtained from recent studies on rats whose pancreatic ducts had 

 been ligated. According to Clowes and Macpherson, 811 these animals de- 

 velop degeneration of the acinar tissue within a month, and exhibit a sig- 

 nificant decrease in intestinal proteolysis, as well as a reduction in the absorp- 

 tion of nitrogenous products and of fats. A "pancreatic factor" containing 

 proteolytic enzymes was shown to restore the normal growth activity of the 

 pancreatic fraction, as a result of the enzymatic liberation of methionine 

 from ingested protein after the reactivation of the proteolytic enzyme in the 

 small intestine. 



According to Rhoads and co-workers, 812 the lipotropic fraction of the pan- 

 creas is markedly active in doses of 60 mg. daily. It appears to be in the 

 category of enzymes, since it is destroyed by boiling its solutions for three 

 minutes. Haanes and Gyorgy 813 demonstrated, by in vitro experiments, 

 the presence of a proteolytic enzyme, probably trypsin, in the pancreatic 

 anti-fatty-liver preparation. These workers likewise postulate that the 

 lipotropic action is based upon enzymatic liberation of methionine from in- 

 gested protein. It is suggested that these findings are in harmony with the 

 assumption that one of the functions of the external pancreatic secretion is 

 to release lipotropic precursors of choline from the protein of the diet. 



(c) Fatty Livers Resulting from an Inositol Deficiency. Inositol, CeH^Oe, 

 is a cyclic hexahydric alcohol. Its importance in nutrition stems from the 

 discovery of Eastcott, 814 in 1928, that it was identical with bios I. Further 

 evidence of its importance in the animal body is that of Woolley, 815 who 

 proved that it is an essential dietary factor for the mouse. A deficiency in 

 this factor produces alopecia in the mouse, 816 and the so-called "spectacle- 

 eye" syndrome in the rat. 816 



The relation of inositol to the lipids was first suggested by Anderson, 817 

 who reported its presence in the lipid isolated from the tubercle bacilli. 

 Klenk and Sakai 818 later identified it as a component of soybean phospho- 



811 G. H. A. Clowes, Jr., and L. B. Macpherson, Am. J. Physiol., 165, 628-638 (1951). 



812 J. E. Rhoads, O. Liboro, S. Fox, P. Gyorgy, and T. E. Machella, Am. J. Physiol, 

 166, 436-440 (1950). 



813 M. L. Haanes and P. Gyorgy, Am. J. Physiol, 166, 441-450 (1950). 



814 E. V. Eastcott, /. Phys. Chem., 32, 1094-1111 (1928). 

 816 D. W. Woolley, Science, 92, 384-385 (1940). 



816 P. L. Pavcek and H. M. Baum, Science, 93, 502 (1941). 



817 R. J. Anderson, J. Am. Chem. Soc, 52, 1607-1608 (1930). 



818 E. Klenk and R. Sakai, Z. physiol. Chem., 258, 33-38 (1939). 



