Effect of administration of alpha- and gamma-tocopherol on tissue distribution and red cell hemolysis in rats.

Four groups of rats fed a tocopherol-free diet from weaning were administered, orally, 1.5 mg/day of either alpha- or gamma-tocopherol for 12 weeks or 5 mg/day of these compounds for 6 weeks. The fifth group was continued on the tocopherol-free diet. At the end of the experimental period the concentration of the two tocopherols was measured in plasma, RBC, liver, kidney, heart, spleen, muscle, testes and lungs. At the lower dose levels alpha-tocopherol, but not gamma-tocopherol, protected the RBC from hemolysis. At the higher levels both compounds were effective in this respect. While liver and spleen appeared to be the preferred storage tissues for both alpha- and gamma-tocopherols, a considerable amount of these compounds were found in RBC, muscle, heart and lung. The content of alpha-tocopherol in the liver was significantly greater than that of gamma-tocopherol. Whether this difference is the reflection of preferential utilization of gamma-tocopherol remains to be determined. The other tissues showed a more or less equal accumulation of the two compounds. At the higher levels of supplementation with the tocopherols the accumulation of gamma-tocopherol in most tissues was significantly greater than that of alpha-tocopherol.