700 XI. VITAMIxNS E (tocopherols) 



in the entire blood of a man was found to amount to 64 mg. while that in a 

 woman was 45 mg.^^ 



The earlier values of Rosenberg^^ are much lower than the more recent 

 figures obtained by using more modern technics based upon plasma rather 

 than upon whole blood. Ames and Harris^ ^^ recorded values ranging from 

 0.9 to 1.2 mg. %, although extreme variations of from 0.1 to 3.0 mg. % 

 sometimes occur. Values of approximately 1 mg. % have also been re- 

 corded by a number of other workers, including Lemley et al.,^^^ Klatskin 

 and Krehl,i-° Darby and co-workers/^ ^ Engel/-- and Couperus.^-^ On the 

 other hand, the results of Varangot et al.^'''^ for plasma vitamin E are quite 

 out of line with those quoted above, being 0.19 mg. % for men and 0.22 

 mg. % for women. There is no explanation for this divergence. 



In the case of cows, somewhat lower values have been observed for the 

 blood tocopherols. Thus, van der Kaay and co-workers'-^ reported a mean 

 level of 800 /j.g. % (0.8 mg. %) for the plasma tocopherol of cows on pasture; 

 this was reduced to 0.1 to 0.2 mg. % (100 to 200 ^g- %) during the winter, 

 when green forage was not available. Meunier, Ferrando, and Chena\der'2^ 

 recorded an average range of 200 to 300 /j,g. % (0.2 to 0.3 mg. %) for sheep. 

 Quaife and associates*^ give the figure 0.7 mg. % as the plasma tocopherol 

 value for male rats on a vitamin E-free diet but receiving 1 mg. of a- 

 tocopherol daily. However, Quaife and Harris'" noted serum tocopherol 

 averages of 1.72 mg. % and 1.68 mg. % for rats whose rations were supple- 

 mented with vitamin E to the extent of 12 mg./week and which were 

 either subjected to stress or were free from stress, respectively. In sharp 

 contrast to these figures, the serum tocopherol was found to be zero in 

 rats which were vitamin E-deficient. For a more complete exposition of 

 the blood tocopherols, including the general physiologic factors to which 



"8 S. R. Ames and P. L. Harris, Intern. Rev. Vitamin Research, 22, 26-34 (1950\ 

 "3 J. M. Lemley, R. G. Gale, R. H. Furman, M. E. Cherrington, W. J. Darby, and 

 G. R. Meneely, Am. Heart J., 37, 1029-1034 (1949). 



120 G. Klatskin and W. A. Krehl, J. Clin. Invest, 29, 1528-1541 (1930). 



121 W. J. Darby, M. E. Cherrington, and J. M. Ruffin, Proc. Soc. Exptl. Biol. Med., 63, 

 310-312(1946). 



122 C. Engel, Ann. New York Acad. Sci., 52, 292-299 (1949). 



123 J. Couperus, Z. Vitaminforsch., 13, 193-207 (1943). 



124 J. Varangot, H. Chailly, and N. Rieux, Com-pt. rend. soc. biol, 137, 210-211 (1943). 



125 F. C. van der Kaay, G. B. H. Teunissen, A. Emmerie, and M. van Eekelen, Ann. 

 New York Acad. Sci., 52, 276-283 (1949). 



12^ P. Meunier, R. Ferrando, and P. Chenavier, Compt. rend. soc. biol., 142, 525-527 

 (1948). 



127 M, L. Quaife and P. L. Harris, Proc. Soc. Exptl. Biol. Med., 78, 188-191 (1951). 



