@misc{oai:repo.qst.go.jp:00067434, author = {Kubota, Yoshihisa and Takahashi, Sentaro and Sato, Hiroshi and Xue, Zhi Sun and 久保田 善久 and 高橋 千太郎 and 佐藤 宏 and 孫 学智}, month = {Aug}, note = {The present study was performed to elucidate the mechanism underlying higher sensitivity of C3H mouse macrophages with respect to irradiation-induced apoptosis. Gamma-irradiation at a dose of 10 Gy induced significant apoptosis in peritoneal resident macrophages (PRMs) of C3H mice 4 hr after irradiation, but not three other strains of mice tested. The induction of apoptosis in PRMs of C3H mice increased in a dose-dependent manner up to 50 Gy, but in PRMs of B6 mice the percentage of apoptosis remained low even at a dose of 100 Gy. On the other hand, hydrogen peroxide induced apoptosis in PRMs of both strains at similar levels. Pretreatment of PRMs of C3H mice with buthionine sulfoximine or N-acetyl cysteine in order to alter the intracellular glutathione level significantly affected hydrogen peroxide-induced apoptosis but had no effect at all on irradiation-induced apoptosis. Sodium formate (a hydroxy radical scavenger) or deferoxamine mesylate (a potent iron chelater) had no effect on irradiation-induced apoptosis but Tiron, a cell permeable superoxide scavenger, significantly interfered with it. The enzymatic activity of superoxide dismutase in the cell lysate of PRMs was measured using a commercial assay kit. The activity of superoxide dismutase was much lower in PRMs of C3H mice than in those of B6 mice. These results suggest that the remarkable irradiation-induced apoptosis observed only in PRMs of C3H mice can be attributed to the lower superoxide dismutase activity and that superoxide among reactive oxygen species produced by ionizing radiation is an important molecule in irradiation-induced apoptosis in PRMs of C3H mice., 第12回国際放射線研究会議}, title = {Mechanism of Higher Incidence of Apoptosis by Irradiation in C3H Mouse Macrophages}, year = {2003} }