Increased haematopoietic stem cell survival in mice injected with tocopherol after X-irradiation.

Tocopherol injection (2.5 mg) immediately after irradiation reduced lethality only during bone-marrow syndrome. Endogenous spleen colony count at 8 days after X-radiation were significantly greater in vitamin-E-injected mice compared to noninjected or vehicle-injected animals; however, 59Fe incorporation into spleen and bone marrow did not suggested enhanced erythropoietic activity in vitamin-E-injected groups at 2,4,8 and 10 days following irradiation. Mitotic index and frequency of micronuclei in marrow at 24 hours post irradiation (3 Gy) were unaffected by tocopherol injection. The uptake of tritium from injected 3H-tocopherol suggests that tocopherol has been accumulated in spleens but not marrows of irradiated animals within a few hours. Also tocopherol has no effect on endogenous spleen colony counts if injected after 5 hours nor is there an effect on the seeding efficiency of exogenous bone-marrow cells injected into recipients receiving tocopherol after irradiation.