PROMOTING EFFECTS OF SODIUM L-ASCORBATE ON 2-STAGE URINARY-BLADDER CARCINOGENESIS IN RATS

  • 1 January 1983
    • journal article
    • research article
    • Vol. 43  (9) , 4454-4457
Abstract
The promoting effect of sodium L-ascorbate on 2-stage urinary bladder carcinogenesis in F344 rats initiated with N-butyl-N-(4-hydroxybutyl)nitrosamine at levels of 0.01 and 0.05% in drinking water was studied. Administration of 5.0% but not of 1.0% sodium L-ascorbate in the diet significantly increased the incidence and number of preneoplastic lesions, papillary or nodular hyperplasia, papilloma and cancer of the urinary bladder. In groups given 5.0% sodium L-ascorbate, the urine was characterized by an apparent elevation of pH, a decrease of osmolality, and an increase of MgNH4PO4 crystalline. Addition of sodium L-ascorbate to the diet also resulted in increase in the content of ascorbic acid and its metabolite, dehydroascorbic acid, in the urine. An extremely high dose of sodium L-ascorbate (5.0%) promotes urinary bladder carcinogenesis under the present experimental conditions, while a high dose (1.0%) does not.