title: Enhancing effect of ethanol on esophageal tumor development in rats by initiation of diethylnitrosamine.
abstract: The effects of ethanol on initiation of esophageal tumorigenesis by diethylnitrosamine (DEN) were investigated in male F344 rats. Animals were administered 50 p.p.m. DEN plus 10% ethanol (Group 1), 33 p.p.m. DEN (Group 2), 50 p.p.m. DEN (Group 3) or 10% ethanol (Group 4) in the drinking water for the first 8 weeks, and were then maintained on basal diet and tap water for up to 104 weeks. The concentration of 33 p.p.m. DEN in Group 2 was an adjustment to the anticipated intake in Group 1. Consequent total intakes of DEN in Groups 2 and 3 were respectively 80% and 134% of that in Group 1. Histopathological examination of esophagus tissue after final sacrifice revealed incidences of papillomas and/or carcinomas in Groups 1, 2 and 3 to be 57.7, 3.8 and 10.7% respectively. No esophageal tumors occurred in Group 4. The incidence of hyperplasia was 100% in Group 1 in contrast to 46.2% in Group 2, 57.1% in Group 3 and 3.6% in Group 4. Thus, the incidences of esophageal proliferative lesions were significantly higher in Group 1 than in Groups 2 or 3. Our results clearly indicate that ethanol has an enhancing effect on the development of esophageal tumors induced by DEN in rats, when administered during the initiation phase.
authors.affiliation: Division of Pathology, National Institute of Hygienic Sciences, Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Aze
authors.forename: K
authors.initials: K
authors.lastname: Toyoda
authors.forename: F
authors.initials: F
authors.lastname: Furukawa
authors.forename: K
authors.initials: K
authors.lastname: Mitsumori
authors.forename: M
authors.initials: M
authors.lastname: Takahashi
mesh_terms: D000818:Animals; D003043:Cocarcinogenesis; D004052:Diethylnitrosamine / Q000633:toxicity*; D004938:Esophageal Neoplasms / Q000139:chemically induced* / Q000473:pathology; D004947:Esophagus / Q000187:drug effects / Q000473:pathology; D000431:Ethanol / Q000633:toxicity*; D006965:Hyperplasia; D008297:Male; D051381:Rats; D011916:Rats, Inbred F344
chemical_list: D004052:Diethylnitrosamine; D000431:Ethanol