On the mechanism of the hepatocarcinogenicity of peroxisome proliferators.
The absence of a genotoxic action in the rat of several peroxisome proliferators (PP) has been confirmed by measuring gross degradation, unscheduled DNA-synthesis (UDS), as well as by measurement of single strand breaks using alkali unwinding in absence and presence of inhibitors of DNA-repair. Similar results were obtained even after drastically lowering the glutathione content of liver. Further, after oral administration of ciprofibrate, no potentiating effect was found in vivo on the generation of micronuclei in hepatocytes by ionizing radiation. The metabolically inert PP, perfluorooctanoic acid, was found to act as a promoter of liver tumors in the rat induced by diethylnitrosamine in an initiation-selection-promotion protocol. The results are discussed in light of available information concerning the mechanism of action of PPs.
Nilsson
R
R
Department of Genetic and Cellular Toxicology, Wallenberg Laboratory, University of Stockholm, Sweden.
Beije
B
B
Préat
V
V
Erixon
K
K
Ramel
C
C
D000818:Animals; D002210:Caprylates / Q000633:toxicity; D002273:Carcinogens; D002994:Clofibrate / Q000633:toxicity*; D002995:Clofibric Acid / Q000031:analogs & derivatives* / Q000633:toxicity; D004247:DNA / Q000187:drug effects; D004249:DNA Damage; D004260:DNA Repair; D058607:Fibric Acids; D005466:Fluorocarbons / Q000633:toxicity; D008099:Liver / Q000187:drug effects; D008113:Liver Neoplasms / Q000139:chemically induced*; D008297:Male; D008830:Microbodies / Q000187:drug effects*; D015162:Micronucleus Tests; D009152:Mutagenicity Tests; D009255:Nafenopin / Q000633:toxicity*; D011839:Radiation, Ionizing; D051381:Rats; D011919:Rats, Inbred Strains; D016196:S Phase / Q000187:drug effects
D002210:Caprylates; D002273:Carcinogens; D058607:Fibric Acids; D005466:Fluorocarbons; D009255:Nafenopin; D002995:Clofibric Acid; D004247:DNA; C023036:perfluorooctanoic acid; C019304:ciprofibrate; D002994:Clofibrate