title: Hydroxyurea-sensitive thymidine incorporation in rat liver and kidney following administration of dimethylnitrosamine.
abstract: In rats treated with dimethylnitrosamine (DMN), the sensitivity of [3H] thymidine incorporation to inhibition by hydroxyurea was determined in the liver and kidney. A 70% inhibition was produced in control animals with doses of hydroxyurea from 50 to 250 mg/kg body wt. Twelve hours after administration of DMN, hepatic thymidine incorporation was unaffected by 50 mg/kg hydroxyurea, progressive reduction in incorporation occurred as the dose of inhibitor was increased. A similar result was obtained in kidney only by dietary conditioning of rats to ensure a high renal metabolism of the DMN. In contrast, at 72 h after DMN treatment thymidine incorporation in both liver and kidney was rapidly inhibited by administration of 50 mg/kg hydroxyurea. The data, assessed together with various parameters of DMN-induced repair and replicative DNA synthesis, suggest the use of hydroxyurea as a means to study DNA repair in intact animals.
mesh_terms: D000818:Animals; D004247:DNA / Q000096:biosynthesis; D004260:DNA Repair / Q000187:drug effects*; D004261:DNA Replication / Q000187:drug effects; D004128:Dimethylnitrosamine / Q000494:pharmacology*; D005260:Female; D006918:Hydroxyurea / Q000494:pharmacology*; D007668:Kidney / Q000187:drug effects / Q000378:metabolism*; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D009602:Nitrosamines / Q000494:pharmacology*; D051381:Rats; D013936:Thymidine / Q000378:metabolism*
chemical_list: D009602:Nitrosamines; D004247:DNA; D004128:Dimethylnitrosamine; D013936:Thymidine; D006918:Hydroxyurea