title: In vivo methylation of guanine by the organophosphorus insecticide tetrachlorvinphos.
abstract: The in vivo methylating capability of the organophosphorus insecticide tetrachlorvinphos, assayed by the formation of 7-methyl-guanine in mouse liver, was investigated. Following intraperitoneal injection of male mice with different doses of the 14C-insecticide, labelled at the OCH3 groups, the total and specific radioactivity of nucleic acids and protein were determined. The 14C-labelling in the isolated macromolecules reached its maximum 24 hours following administration of the insecticide. Analysis of the acid hydrolysate of DNA and of RNA on Dowex-50 WX-12 revealed the presence of (7-14C) methylguanine. At maximum 14C-labelling, the amount of radioactive 7-MeGu, calculated as fraction of total dose, was around 9 X 10(-5) and 39 X 10(-5) for DNA and RNA, respectively.
mesh_terms: D000818:Animals; D004247:DNA / Q000378:metabolism; D006147:Guanine / Q000378:metabolism*; D008099:Liver / Q000378:metabolism; D008297:Male; D008745:Methylation; D051379:Mice; D001074:Propoxur / Q000032:analysis*; D011506:Proteins / Q000378:metabolism; D012313:RNA / Q000378:metabolism; D013751:Tetrachlorvinphos / Q000633:toxicity*
chemical_list: D011506:Proteins; D006147:Guanine; D012313:RNA; D004247:DNA; D001074:Propoxur; D013751:Tetrachlorvinphos