title: Enhancement by Wy-14,643, a hepatic peroxisome proliferator, of diethylnitrosamine-initiated hepatic tumorigenesis in the rat.
abstract: Diethylnitrosamine (DEN), at a concentration of 100 parts/10(6) in drinking water for 14 days, caused the development, by 48 weeks, of very few liver tumours in 5 of 18 (27%) male F=344 rats fed control diet. When the DEN treatment was followed one week later by continuous feeding of the hypolipidemic hepatic peroxisome proliferator, Wy-14,643, at 0.1% dietary level, all of 28 rats (100%) developed, between 38 and 48 weeks, a significantly higher number of liver tumours. Furthermore, laparotomy at 22 weeks revealed that several rats fed Wy-14,643 after DEN initiation had developed visible liver nodules, suggesting that Wy-14,643 also accelerates the appearance of these tumours. Administration of another peroxisome proliferator, clofibrate, at 0.5% level in the diet after DEN initiation, also caused a substantial enhancement of liver tumorigenesis. The enhancement of liver-tumour development by clofibrate, however, was less than that by Wy-14,643. The marked enhancing effect of Wy-14,643 may be due to its profound hepatomegalic and peroxisome proliferative properties.
mesh_terms: D000085:Acetates / Q000494:pharmacology; D000818:Animals; D002455:Cell Division; D002994:Clofibrate / Q000633:toxicity; D004052:Diethylnitrosamine / Q000633:toxicity*; D004357:Drug Synergism; D008099:Liver / Q000473:pathology; D008113:Liver Neoplasms / Q000139:chemically induced* / Q000473:pathology; D008114:Liver Neoplasms, Experimental / Q000139:chemically induced* / Q000473:pathology; D008297:Male; D009602:Nitrosamines / Q000633:toxicity*; D011743:Pyrimidines / Q000494:pharmacology*; D051381:Rats; D011916:Rats, Inbred F344
chemical_list: D000085:Acetates; D009602:Nitrosamines; D011743:Pyrimidines; D004052:Diethylnitrosamine; C006253:pirinixic acid; D002994:Clofibrate