FATS AS ESSEXTIAL DIETARY COMPONENTS 863 



wheat germ oil and cod liver oil, in conjunction with propyl thiouracil. 

 A definite remission of the glycosiu'ia was noted, without the loss of bod^^ 

 weight which might otherwise be expected. ^^ However, the protective 

 effect of thiouracil, of propyl thiouracil, of thyroidectomy, and also of 

 estradiol benzoate, against pancreatic and alloxan diabetes was noted 

 even when the animals were fed nd lihitiDii on diets containing only small 

 amounts of these fats.^^~^" 



In the case of the lard-fed animals, the addition of choline or of sulfon- 

 amide to the diet, or an increase in the protein ration, did not reduce the 

 toxicity. When the rats were fed diets high in olive oil or butter, the 

 effect of alloxan was not modified, but there was a slight decrease in mor- 

 tality when oleomargarine or corn oil was given, and the mortality was 

 zero when coconut oil (34%) was fed.^^ Houssay^^ found that, in human 

 subjects, as well as in animals, "certain fats" (which he did not identify) 

 favored the development of alloxan and pancreatic diabetes, while others 

 inhibited it. In general, a pre^'ious diet poor in carbohydrates and rich in 

 fats decreased the utilization of the carbohydrates, and the response to 

 insulin.^* 



It would appear that, when short-chain fattj^ acids are fed, such as 

 those which occur in coconut oil, an improvement in alloxan diabetes is 

 to be expected, while no change is noted, or the symptoms are more severe, 

 when the usual fats containing long-chain fatty acids are included in the 

 diet. Later reports from the South American laboratory indicated that 

 the higher the degree of unsaturation of the fatty acids in the various fats 

 and oils, the higher was the incidence of diabetes.^^"'''' Rodriguez et al.^°'^ 

 noted, for example, that diabetes occurred in from to 12% of rats fed 

 alloxan (40 mg./kg. body weight) in conjunction with caprylic + capric 

 acid esters (0%), palmitic + stearic acid (12%), and palmitic + stearic 

 acid esters (5%), while the incidence increased up to 100% in the case of 

 animals receiving alloxan (160 mg. ^kg.) with fats containing fatty acids 



9^ C. Martinez, Rev. soc. anjentina hioL, 27, 14-18 (1951). 



«* R. R. Rodriguez and C. Martinez, Rev. soc. argentina bioL, 26, 127-134 (1950). 



96 C. Martinez, Rev. soc. argentina biol.,-22, 135-146 (1946). 



" B. A. Honssav, V. G. Foglia, H. P. Diaz, and J. G. Sara, Rev. soc. argentina bioL. 21, 

 232-242(1945). 



9' B. A. Houssay, Rev. asoc. med. argentina, 64, 1-19 (1950). 



'^ R. R. Rodriguez, P. Cattaneo, B. A. Houssay, and B. Uno, Rev. soc. argentina bioL, 

 ^5,224-230(1952). 



"» R. R. Rodriguez and W. A. Krehl, Am. J. Physiol, 169, 295-300 (1952). 



'"' R. R. Rodriguez, personal communication cited by L. F. Leloir and C. E. Cardini, 

 Ann. Rev. Biochem., 22, 1 79-210 (1953), p. 202. 



'"^ R. R. Rodriguez, P. Cattaneo, B. A. Houssaj', and B. Uno, J. Nutrition, 51, 441-448 

 (1953). 



