732 XI. VITAMINS E (tocopherols) 



the tocopherol causes an enhancement in the synthesis or in the turno\'er 

 rate of CoA. 



D-a-Tocopherol was found by Hove'"'" to decrease markedly the toxicity 

 of carbon tetrachloride for rats on a 10% casein, vitamin E-free diet. The 

 a-form exhibited a much better protective action than did D-7-tocopherol. 

 Other compounds which exerted a similar or moderate protective action 

 included theophylline (1,3-dimethylxanthine), xanthine, and guanine, 

 while hypoxanthine and theobromine (3,7-dimethylxanthine) were in- 

 active. DL-Methionine was likeAvise active, while negative results were 

 obtained with glycine and arginine. 



j. The Role of Vitamin E in Kidney Nephrosis. Martin and Moore ^"^ 

 were the first to call attention to the nephrotic syndrome which develops 

 in the outer cortex of the kidneys of rats receiving a low-vitamin E diet, 

 after three or four months of deficiency, and which becomes generalized 

 after ten months. Although the glomeruli show no changes, the tubular 

 epithelia become coarsely granular, irregular in contour, and are separated 

 from the basement membrane. Acid-fast pigment is laid down in the 

 Pa^^ 199, 203 nionkey,^^* and mink^^® in the absence of nephrotic changes. 

 EmmeP^""^ suggested that the kidneys of rats raised on low vitamin E 

 diets which are high in long-chain unsaturated acids (such as those m cod- 

 liver oil, or the fatty acids of linseed oil) are subject to much more rapid 

 postmortem autolysis than are kidneys of rats which have received dietary 

 tocopherol. The tissue tocopherol levels of these rats,^^- as in the case 

 of the tissues from calves^^^ having a cod-liver oil-induced dystrophy, is 

 not lower than in tissues from control animals on a lard diet. Although 

 tocopherol therapy over a relatively short period will not re\'erse the rapid 

 kidney autolysis, supplementation with this vitamin over the whole period 

 will effectively prevent the development of this abnormal condition. 



k. The Role of Vitamin E in Preventing Stomach Ulcers. Hyperplastic 

 ulcer-like lesions can be produced in the rumen of the rat under a wide 

 assortment of nutritional disorders; these were reviewed by Zucker et al.^"^^ 

 It was suggested that in most cases a low protein level in the diet appeared 

 to be a critical factor in producing this disorder. Zucker and co-workers"^ 



5«8 E. L. Hove, Arch. Biochem., 17, 467-474 (1948). 



"" V. M. Emmel, Anat. Record, 118, 384-385 (1954); 121, 289-280 (1955). 



^^1 V. M. Emmel, Kidney Autolysis in Vitamin E-Deficient Rats Receiving a Diet Rich 

 in Unsaturated Fatty Acids. Abst. Reports Third Intern. Congr. on Vitamin E, Venice, 

 1955, Vol. I, p. 31. 



^^2 V. M. Emmel, personal communication cited by P. L. Harris and K. E. Mason in 

 Proc. Third Intern. Congr. on Vitamin E, Venice, 1955, Valdonega, 1956, p. 13. 



3" T. F. Zucker, B. N. Berg, and L. M. Zucker, J. Nutrition, SO, 319-331 (1945). 



