The effect of total body irradiation on the occurrence of chemically induced tumors in mice of inbred strains with different activabilities of the AHH system.
On four strains of inbred mice (C57B1/6, C57B1/10, C3H and DBA2), which were chosen according to their genetically conditioned activability of the arylhydrocarbonhydroxylase system (AHH) the effect was checked of repeated whole body exposure to 60Co gamma rays on the occurrence and origination of the formation of tumors induced by methylcholanthrene. Mice of the strains C57B1/6, C57B1/10 and C3H have a high activability of the AHH system, those of the strain DBA2 exert a low activability. The experiment was supposed to check, how much is the damage of the immunological reactivity induced by radiation able to affect carcinogenic effects of methylcholanthrene. The repeated whole body irradiation of mice neither increased the rate of occurrence of tumors nor affected the time of origination of growth of tumors induced with methylcholanthrene. These results indicate that in the formation of tumors induced with methylcholanthrene, there is a prevalent role of genetically conditioned metabolism of the precarcinogen and not of an intervention into immunologic processes in the organism resulting from the whole body irradiation.
D000818:Animals; D001189:Aryl Hydrocarbon Hydroxylases / Q000528:radiation effects*; D004789:Enzyme Activation / Q000187:drug effects / Q000528:radiation effects; D005260:Female; D005720:Gamma Rays; D007928:Lethal Dose 50; D007958:Leukocyte Count / Q000187:drug effects / Q000528:radiation effects; D008297:Male; D008748:Methylcholanthrene; D051379:Mice; D008815:Mice, Inbred Strains / Q000378:metabolism*; D009374:Neoplasms, Experimental / Q000139:chemically induced / Q000201:enzymology* / Q000276:immunology; D011836:Radiation Tolerance; D013997:Time Factors; D014916:Whole-Body Irradiation
D008748:Methylcholanthrene; D001189:Aryl Hydrocarbon Hydroxylases