title: Effect of vitamin A acetate on urinary bladder carcinogenesis induced by N-butyl-N-(4-hydroxybutyl)nitrosamine in rats.
abstract: The effect of vitamin A acetate on the urinary bladder carcinogenicity of N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) was determined in male Wistar rats. Vitamin A acetate at the dose administered induced no changes in the urinary bladder or other organs when administered without the carcinogen. However, hypervitaminosis A inhibited keratinization and squamous metaplasia in bladder lesions induced by BBN, and the incidence of transitional cell carcinoma and papilloma of the urinary bladder was significantly reduced at a dose greater than 100 IU/g diet (P less than 0.02). The present experiment suggests that for the urinary bladder epithelium of rats hypervitaminosis A reduced susceptibility to the tumorigenicity of BBN.
mesh_terms: D000818:Animals; D002085:Butylhydroxybutylnitrosamine; D002295:Carcinoma, Transitional Cell / Q000139:chemically induced / Q000517:prevention & control*; D008297:Male; D009374:Neoplasms, Experimental / Q000139:chemically induced / Q000517:prevention & control; D009602:Nitrosamines; D010212:Papilloma / Q000517:prevention & control; D051381:Rats; D001743:Urinary Bladder / Q000473:pathology; D001749:Urinary Bladder Neoplasms / Q000139:chemically induced / Q000473:pathology / Q000517:prevention & control*; D014801:Vitamin A / Q000008:administration & dosage*
chemical_list: D009602:Nitrosamines; D014801:Vitamin A; D002085:Butylhydroxybutylnitrosamine