Enhancement of O2- production from resident peritoneal macrophages by low-dose in vivo gamma-irradiation.
Superoxide anion (O2-) production after very low-dose in vivo irradiation (4 cGy) was examined in resident peritoneal macrophages. The level of production rapidly increased following treatment with the PKC activator, phorbol 12-myristate 13-acetate (PMA), but no further enhancement by low-dose in vivo irradiation was observed. On the other hand, treatment with zymosan A gradually induced O2- production, which was further increased in low-dose in vivo irradiated macrophages. The amounts of phagocytosis of zymosan A were not changed by in vivo irradiation. This indicated that the enhancement of O2- production was not due to an increase in phagocytotic activity by low-dose in vivo irradiation. Our results show that low-dose in vivo irradiation induces production of reactive oxygen species by macrophages, not only nitric oxide as reported in our previous paper but also O2-. This may contribute to the increase of cytolytic activity of macrophages after low-dose in vivo irradiation.
Ibuki
Y
Y
Laboratory of Radiation Biology, Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Japan. ibuki@sea.u-shizuoka-ken.ac.jp
Goto
R
R
D000818:Animals; D004789:Enzyme Activation / Q000528:radiation effects; D005720:Gamma Rays; D017737:Macrophages, Peritoneal / Q000378:metabolism / Q000528:radiation effects*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D019255:NADPH Oxidases / Q000528:radiation effects; D011493:Protein Kinase C / Q000502:physiology; D013481:Superoxides / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D015054:Zymosan / Q000378:metabolism
D013481:Superoxides; D015054:Zymosan; D019255:NADPH Oxidases; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate