title: Failure of dietary alpha-difluoromethylornithine to inhibit gastric carcinogenesis in rats after 8 weeks of treatment with N-methyl-N'-nitro-N-nitrosoguanidine and sodium chloride.
abstract: The modifying effects of alpha-difluoromethylomithine (DFMO) on glandular stomach carcinogenesis after initiation with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and sodium chloride were investigated in male outbred Wistar rats. Animals were simultaneously given MNNG solution (100 ppm) as their drinking water and diet supplemented with 10% sodium chloride for 8 weeks, and administered DFMO (dietary levels of 2000 ppm or 500 ppm) and tap water for the following 70 weeks. The DFMO treatment did not show any tendency to inhibit the development of gastric adenocarcinomas. The incidences and multiplicities of atypical hyperplasias in the glandular stomachs were also comparable in all groups of rats given MNNG/sodium chloride. Neither gastric carcinomas nor atypical hyperplasias were observed without the carcinogen treatment. Thus, DFMO did not exert any inhibitory effects when given during the post-initiation phase of two-stage glandular stomach carcinogenesis in rats initiated with MNNG and sodium chloride for 8 weeks.
authors.affiliation: Division of Pathology, National Institute of Health Sciences, Tokyo, Japan.
authors.forename: Z
authors.initials: Z
authors.lastname: Tanakamaru
authors.forename: A
authors.initials: A
authors.lastname: Nishikawa
authors.forename: F
authors.initials: F
authors.lastname: Furukawa
authors.forename: T
authors.initials: T
authors.lastname: Imazawa
authors.forename: I S
authors.initials: IS
authors.lastname: Lee
authors.forename: K
authors.initials: K
authors.lastname: Kasahara
authors.forename: T
authors.initials: T
authors.lastname: Tanaka
authors.forename: M
authors.initials: M
authors.lastname: Takahashi
mesh_terms: D000230:Adenocarcinoma / Q000517:prevention & control*; D000818:Animals; D002455:Cell Division / Q000187:drug effects; D018890:Chemoprevention; D000518:Eflornithine / Q000627:therapeutic use*; D008297:Male; D008769:Methylnitronitrosoguanidine; D051381:Rats; D017208:Rats, Wistar; D012965:Sodium Chloride; D013274:Stomach Neoplasms / Q000517:prevention & control*
chemical_list: D008769:Methylnitronitrosoguanidine; D012965:Sodium Chloride; D000518:Eflornithine