Lack of promotion of urinary bladder carcinogenesis by sodium bicarbonate andor l-ascorbic acid in male ODSShi-odod rats synthesizing α2μ-globulin but not l-ascorbic acid》.pdfVIP

Pergamon Food and Chemical Toxicology 35 (1997) 783-787 Lack of Promotion of Urinary Bladder Carcinogenesis by Sodium Bicarbonate and/ or L-Ascorbic Acid in Male ODS/Shi-od/od Rats Synthesizing c 2 ,-Globulin but not L-Ascorbic Acid S. MORI*, T. MURAI*f, M. HOSONOf, S. MACHINOf, S. MAKINOt, C. CHOU* and S. FUKUSHIMA*:~ *First Department of Pathology, Osaka City University Medical School, Asahi-machi, Abeno-ku, Osaka 545 aad fAburahi Laboratories, Shionogi Research Laboratories, Shionogi Co., Ltd, Koka- cho, Shiga 520-34, Japan (Accepted 18 December 1996) Abstract--The study was designed to investigate whether sodium bicarbonate (NaHCO3) and/or L- ascorbic acid (AsA) promote urinary bladder carcinogenesis in male ODS/Shi-od/od (ODS) rats, which, unlike male F344 rats, are resistant to sodium L-ascorbate (Na-AsA)-promoting effects. Whereas F344 rats can synthesize AsA and ~2u-globulin (A2u-G), only A2u-G is produced in ODS rats. The two strains were given 0.05% N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) in their drinking water for 2 wk and then were fed basal CA-I diet supplemented with 3% NaHCO3 plus 5% AsA (NaHCO3 + AsA), 3% NaHCO3, 5% AsA, or no chemicals for 32 wk.