title: Dose-dependent promoting activity of chloroform in rat liver foci bioassay.
abstract: Chloroform enhances dose-dependently the number of preneoplastic foci in livers of weanling female Sprague-Dawley rats. The preneoplastic foci were induced with a single dose of 8 mg diethylnitrosamine (DEN)/kg body wt. Thereafter chloroform was applied twice weekly for 11 consecutive weeks in doses of 100, 200 and 400 mg/kg body wt, respectively. This treatment raised the number of adenosine-5'-triphosphatase (ATPase)-deficient foci up to 5-fold, that of gamma-glutamyltranspeptidase (GGTase) and glycogen-positive foci 13- and 10-fold, respectively, after 12 weeks; 25 mg caused no effect compared to DEN-treated controls. In contrast, daily doses of chloroform only, 200 and 400 mg/kg body wt for 33 days, and 800 mg/kg body wt for 20 days given to 3-4-week-old female Sprague-Dawley rats did not lead to island formation, measured after 12 weeks, indicating a promoting rather than an initiating potency.
authors.forename: E
authors.initials: E
authors.lastname: Deml
authors.forename: D
authors.initials: D
authors.lastname: Oesterle
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D000818:Animals; D002273:Carcinogens; D002725:Chloroform / Q000633:toxicity*; D003043:Cocarcinogenesis; D004052:Diethylnitrosamine / Q000633:toxicity; D005260:Female; D006003:Glycogen / Q000378:metabolism; D008113:Liver Neoplasms / Q000139:chemically induced* / Q000201:enzymology; D011230:Precancerous Conditions / Q000139:chemically induced* / Q000201:enzymology; D051381:Rats; D011919:Rats, Inbred Strains; D005723:gamma-Glutamyltransferase / Q000378:metabolism
chemical_list: D002273:Carcinogens; D004052:Diethylnitrosamine; D002725:Chloroform; D006003:Glycogen; D005723:gamma-Glutamyltransferase; D000251:Adenosine Triphosphatases