title: Preventive effect of magnesium hydroxide on carcinogen-induced large bowel carcinogenesis in rats.
abstract: Preventive effect of magnesium hydroxide on carcinogen-induced, large bowel carcinogenesis was examined in three experiments using F344 rats. Experiment I: Rats received dietary administration of magnesium hydroxide at concentrations of 500 or 1,000 ppm after treatment with methylazoxymethanol (MAM) acetate (25 mg/kg, 3 times). These rats had a lower incidence of large bowel neoplasms than animals given MAM acetate alone. Reduction of the tumor incidence was especially significant at a dose of 500 ppm. Experiment II: Rats given magnesium hydroxide (250, 500, or 1,000 ppm) together with 1,2-dimethylhydrazine (DMH) (20 mg/kg, 10 times) showed a lower multiplicity of large bowel tumors than those given DMH alone. Experiment III: The labeling indices of the cryptal cells of the large bowel (cecum or proximal colon or distal colon) or rates given magnesium hydroxide for 4, 6, or 8 weeks after treatment with MAM acetate (25 mg/kg, 3 times) were smaller than those of animals given MAM acetate alone, indicating that magnesium hydroxide suppressed, carcinogen-induced epithelial cell (large bowel) proliferation. The results of the three experiments suggest that magnesium, one of the essential metals, is a promising chemopreventive agent in humans.
authors.affiliation: Department of Pathology, Gifu University School of Medicine, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Mori
authors.forename: Y
authors.initials: Y
authors.lastname: Morishita
authors.forename: T
authors.initials: T
authors.lastname: Shinoda
authors.forename: T
authors.initials: T
authors.lastname: Tanaka
mesh_terms: D000230:Adenocarcinoma / Q000139:chemically induced / Q000517:prevention & control; D000236:Adenoma / Q000139:chemically induced / Q000517:prevention & control; D000818:Animals; D016588:Anticarcinogenic Agents / Q000494:pharmacology*; D003106:Colon / Q000187:drug effects / Q000473:pathology; D003110:Colonic Neoplasms / Q000139:chemically induced / Q000517:prevention & control*; D004127:Dimethylhydrazines / Q000633:toxicity*; D008276:Magnesium Hydroxide / Q000494:pharmacology*; D008297:Male; D008746:Methylazoxymethanol Acetate / Q000633:toxicity*; D008940:Mitotic Index / Q000187:drug effects; D051381:Rats; D011916:Rats, Inbred F344
chemical_list: D016588:Anticarcinogenic Agents; D004127:Dimethylhydrazines; D008746:Methylazoxymethanol Acetate; D008276:Magnesium Hydroxide