Lack of Influence of Testicular Castration or Sialoadenectomy on Sodium L-Ascorbate Promotion of Urinary Bladder Carcinogenesis in Male F344 Rats

The study was designed to investigate whether testicular castration (TC) or sialoadenectomy (SE) can influence sodium L-ascorbate (Na-AsA)-promoting effects on urinary bladder carcinogenesis in male F344/DuCrj rats. The animals, 6 weeks old at the commencement of the treatment, were given 0.05% N-butyl-N- (4-hydroxybutyl)nitrosamine (BBN) in their drinking water for 4 weeks and then subjected to TC or SE. Thereafter they received basal diet with or without 5% Na-AsA supplement for 32 weeks. Na-AsA caused significant increase in urinary pH, the concentrations of sodium ion, and total ascorbic acid, whereas these urinary parameters were not influenced by TC and SE. TC significantly decreased the relative organ weights of the accessory sexual glands, kidneys, and livers whereas SE was without effect on these organs. TC and SE decreased very slightly BBN-induced carcinogenesis, but TC and SE did not influence the Na-AsA-promoting effects. The present results indicate that Na-AsA-promotion of two-stage urinary bladder carcinogenesis does not depend on the presence of testes or salivary glands.