Abstract: | The protective efficacy of an orally administered bovine protein-free parathyroid extract (PF-PTE) was studied on rat bone marrow cells in vivo with the mitotic index after 850 R irradiation. A remarkable decrease was found in the mitotic activity of bone marrow cells after irradiation in the non-protected animals. However, in the animals treated with PF-PTE after irradiation, a significantly smaller decrease and a faster recovery were found in the mitotic activity of the bone marrow cells. |