title: Effect of copper administration on the incorporation of [3H]-thymidine into the liver DNA of rats stimulated by dimethylnitrosamine and diethylnitrosamine.
abstract: The incorporation of [3H]thymidine into liver DNA of rats increased 6--8 times 48 h after a single injection of dimethylnitrosamine (DMN, 30 mg/kg) and diethylnitrosamine (DEN, 100 mg/kg). To test the suppressive effect of copper, the incorporation of [3H]thymidine into liver DNA in the DMN groups or DEN groups pretreated with copper was measured 48 h after the administration of DMN or DEN. The incorporation of [3H]thymidine into liver DNA of rats stimulated by the injection of DMN was strikingly suppressed by the injection of cupric acetate (20 mg Cu/kg), but that of rats stimulated by the injection of DEN was not suppressed by the injection of copper. Some other metal salts, silver nitrate (20 mg Ag/kg), nickel acetate (20 mg Ni/kg) and basic lead acetate (20 mg Pb/kg) did not significantly suppress the incorporation of [3H]thymidine stimulated by DMN or DEN. The accumulation of copper was much higher in the liver of copper-administered rats than that of nickel or lead in the liver of nickel-administered rats or lead-administered rats. The accumulation of silver was comparatively high in the liver of silver-administered rats.
mesh_terms: D000818:Animals; D003300:Copper / Q000494:pharmacology*; D004261:DNA Replication / Q000187:drug effects*; D004052:Diethylnitrosamine / Q000494:pharmacology*; D004128:Dimethylnitrosamine / Q000494:pharmacology*; D007700:Kinetics; D007854:Lead / Q000494:pharmacology; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D009532:Nickel / Q000494:pharmacology; D009602:Nitrosamines / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D012834:Silver / Q000494:pharmacology; D013936:Thymidine / Q000378:metabolism; D014316:Tritium
chemical_list: D009602:Nitrosamines; D014316:Tritium; D007854:Lead; D004052:Diethylnitrosamine; D012834:Silver; D003300:Copper; D009532:Nickel; D004128:Dimethylnitrosamine; D013936:Thymidine