VII. EFFECTS OF DEFICIENCY 555 



b. Tissue Tocopherols 



Tisfc^ue levels of tocopherols, especially those of the major storage depots, 

 are undoubtedly the most reliable index of vitamin E imtriturc. The usual 

 method for analysis of tocopherols in foods and tissues^"^ is laborious and 

 time-consuming. Tissues obtainable are limited to postmortem material, 

 except Nvhere generous biopsy samples can be secured. Although c?-a-tocoph- 

 erol is the predominant type found in tissues, variable but usually not 

 very large amounts of 7- and 5-tocopherols are also present ;^^^"^^^ however, 

 results are generally expressed in terms of total tocopherols. 



Information concerning tocopherols in human tissues is limited to anal- 

 yses carried out by Abderhalden^'^'^ on a ^'ariety of tissues from fetuses, 

 newborn, and adults, those of Quaife and Dju'*^ on two cases of accidental 

 death, and a more extensive series of analyses covering the period from 

 early fetal life to old age,^"-^^^ carried out in the writer's laboratory. The 

 results of these studies indicate that tocopherols are widely distributed in 

 human tissues from early fetal life to advanced old age. Tocopherol levels, 

 expressed as milligrams per 100 g. of fresh tissue, are low in fetuses of 2 to 

 6 months' gestation age, and only slightly higher in premature and full 

 term infants at birth. The data obtained are in accord with other evidence 

 that during the early postnatal period of life states of suboptimal vitamin 

 E nutriture may occur. During early postnatal life, tissue levels tend to 

 increase slowly unless suppressed by disease of various types. During child- 

 hood and adolescence they reach levels comparable to those of adults 

 which, for muscle, heart, liver, and certain other visceral organs, are ap- 

 proximately twice those at birth, and for adipose tissue are considerably 

 higher than in other tissues, with the exception of the adrenal. Both pitui- 

 tary and testis contain about four times as much tocopherol per unit of 

 fresh tissue as do other \-isceral organs, but only about one-third as much 

 as the adrenal. During the latter few decades of life there appears to be a 

 tendencj^ for tocopherols to diminish somewhat in liver and in adipose 

 tissue. It is also of interest that total tocopherols (expressed as milligrams 

 per 100 g. of fresh tissue) in skeletal muscle, heart, liver, and other \-isceral 

 organs, except the endocrine glands mentioned, are of about the same order 

 as observed in the circulating blood. 



On the other hand,when tocopherols are expressed as milligrams per 

 gram of extractible fat the values for adipose tissue are considerably lower 

 than for most of thetissues just mention(>d, whereas the values for pituitary, 

 testis, and adrenal appear to be considerably higher. Although tocopherols 

 in adipose tissue appear to increase during early life on the basis of tocoph- 

 erols per unit of fresh tissue, andtodiminishintermsof tocopherols per unit of 

 extractible fat, from a quantitative standpoint the adipose tissue of the 



"•>M. L. Quaife and I'. L. Harris, Anal. Chem. 20, 1221 (1948). 



