Effect of pretreatment with cysteamine on gamma-radiation-induced sister chromatid exchanges in mouse bone marrow cells in vivo.
The effect of pretreatment with cysteamine on gamma-radiation-induced sister chromatid exchanges (SCEs) and on the mitotic index and average generation time was determined. Groups of mice were treated in one of the following regimens: (1) irradiated, (2) treated with cysteamine and irradiated, (3) treated with cysteamine only, or (4) left untreated. Intraperitoneal administration of cysteamine preceding gamma-radiation exposure protected against SCE induction. However, radioprotection was not reflected by change in the mitotic index or in the average generation time. The results suggest that, under the experimental conditions of this study, the SCEs are caused by free radicals produced by gamma radiation, but not the additional damage indices measured.
Mendiola-Cruz
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MT
Departamento de Radiobiología, Instituto Nacional de Investigaciones Nucleares, México, D.F.
Morales-Ramírez
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P
D000818:Animals; D001853:Bone Marrow / Q000187:drug effects / Q000528:radiation effects*; D001854:Bone Marrow Cells; D003037:Cobalt Radioisotopes; D003543:Cysteamine / Q000494:pharmacology*; D005720:Gamma Rays; D008297:Male; D008677:Metaphase / Q000187:drug effects / Q000528:radiation effects; D051379:Mice; D008807:Mice, Inbred BALB C; D008940:Mitotic Index / Q000187:drug effects / Q000528:radiation effects; D012854:Sister Chromatid Exchange / Q000187:drug effects / Q000528:radiation effects*; D013997:Time Factors
D003037:Cobalt Radioisotopes; D003543:Cysteamine