title: Formation by diethylnitrosamine and persistence of O4-ethylthymidine in rat liver DNA in vivo.
abstract: The formation by diethylnitrosamine (DEN) and persistence of O4-ethylthymidine in rat liver DNA in vivo has been studied using enzymic hydrolysis of DNA, cation exchange column chromatography and thin-layer chromatography (TLC). The amount of O4-ethylthymidine represented about 1% of the total ethylation; its half-life in vivo was 19 (range 16--24) days, the same value as obtained for O2-ethylthymidine. The persistence of O2- and O4-ethylthymidine, rather than the rapid removal of O6-ethylguanine, favours the former miscoding base adducts as relevant molecular lesions in rat liver carcinogenesis.
mesh_terms: D000478:Alkylation; D000818:Animals; D004247:DNA / Q000378:metabolism*; D004052:Diethylnitrosamine / Q000378:metabolism*; D005260:Female; D008099:Liver / Q000378:metabolism*; D009602:Nitrosamines / Q000378:metabolism*; D051381:Rats; D013936:Thymidine / Q000031:analogs & derivatives* / Q000378:metabolism
chemical_list: D009602:Nitrosamines; D004052:Diethylnitrosamine; C030119:O(4)-ethylthymidine; D004247:DNA; D013936:Thymidine