Radioprotection by superoxide dismutase of macrophage progenitor cells from mouse bone marrow.
X-ray survival of cultured macrophage progenitor cells from mouse bone marrow was represented by a two-component curve, both in the absence and presence of superoxide dismutase. Protection by the enzyme was limited to the radiosensitive fraction, for which a dose modifying factor of 2.8 +/- 0.7 was obtained. Catalase did not protect. Survival of the radiosensitive fraction, with and without exogenous superoxide dismutase, was temperature-dependent, whereas that of the radioresistant fraction was not. In the former case, the energy required for the enzyme-treated cells was approximately 13kJ/mol.
D000818:Animals; D001853:Bone Marrow / Q000201:enzymology / Q000528:radiation effects; D002470:Cell Survival / Q000528:radiation effects; D002478:Cells, Cultured; D004307:Dose-Response Relationship, Radiation; D006412:Hematopoietic Stem Cells / Q000201:enzymology* / Q000528:radiation effects; D008264:Macrophages / Q000201:enzymology* / Q000528:radiation effects; D051379:Mice; D011837:Radiation-Protective Agents; D013482:Superoxide Dismutase / Q000378:metabolism*; D013696:Temperature
D011837:Radiation-Protective Agents; D013482:Superoxide Dismutase