Plasma and tissue levels of dietary radiotocopherols in the harp seal, Phoca groenlandica.

Plasma and tissue levels of dietary radiotracer-labeled tocopherols were examined in the harp seal, Phoca groenlandica. The d-alpha form showed much higher plasma maxima and retention than d,l-gamma-tocopherol. Concentration peaks occurred somewhat later but were greater when the vitamin was fed with Tween 80 than with herring and corn oil respectively. Greater plasma levels occurred with the use of herring oil as compared with corn oil. Seals previously maintained on a vitamin E deficient diet showed greater plasma maxima than seals not so deprived. Plasma and tissues generally showed maximum levels within 24 h postingestion. Tissue levels of labelled dietary alpha-tocopherol were examined by biopsy and postmortem studies in selected tissues of vitamin E deprived seals.