Radioprotection of hemopoietic stem cells (CFUs) at partial irradiation

In mice irradiated with the left hind leg shielded, the protective effectiveness of mexamine on the formation of macroscopic colonies of the hemopoietic tissue in the spleen was determined. In applying mexamine 10 minutes prior to partial irradiation, the total number of colonies is a result of the additive action of radioprotection and a repopulation of the spleen from the shielded bone marrow. The repair of the sublethal damage of splenic CFUs is induced by the hemopoietic tissue of the shielded bone marrow, which is reflected by an increased number of colonies at a time when a protective effect of mexamine could no longer be observed. (author)