Tocopherol level in human blood cells.

The study was undertaken on alpha-tocopherol levels, separated from other analogs, in the red blood cells (RBC) of cord blood, premature infants, healthy children and adults as well as in pregnant women, and compared with the plasma levels. 1. The majority of tocopherol found in the RBC was localized in the membranes. 2. Only alpha-tocopherol was found in the RBC, while alpha- and gamma-tocopherol were found in the plasma. 3. Alpha-tocopherol level in the RBC changes during development in parallel with that in the plasma. However, changes in the level in RBC were smaller than those of the plasma. 4. The ratio of alpha-tocopherol level in the RBC to the plasma was higher in the cord blood and premature infants than in the children and adults. 5. With regard to the cases with high plasma tocopherol levels, a different finding was obtained on the RBC level between pregnant women and adults with a large amount of tocopherol. In the latter, high RBC levels were observed as the plasma levels were elevated, while in spite of a high plasma tocopherol level, the lowest RBC levels were found in the pregnant women.