Susceptibility of Four F sub(1) Hybrids of Male Rats to the Promoting Effects of Sodium L-ascorbate in Two-Stage Urinary Bladder Carcinogenesis

• Published in: Journal of toxicologic pathology Vol. 19; no. 2; p. 87
• Main Authors: Mori, Satoru, Murai, Takashi, Wanibuchi, Hideki, Hagiwara, Akihiro, Puatanachokchai, Rawiwan, Fukushima, Shoji
• Format: Journal Article
• Language: English
• Published: 01.01.2006
• ISSN: 0914-9198

In the two-stage rat urinary bladder carcinogenesis model with N-butyl-N-(4- hydroxybutyl)nitrosamine (BBN) as an initiator and sodium L-ascorbate (Na-AsA) as a promoter, we previously reported that F344/DuCrj (F344) and LEW/Crj (Lewis) rats were sensitive, whereas WS/Shi (WS) and ODS/Shi-od/od (ODS) rats were resistant. In the present study, for the development of a model useful to the QTL analysis of host genes, we examined the susceptibility to Na-AsA promotion in (F344 x WS)F sub(1), (F344 x ODS)F sub(1), (Lewis x WS)F sub(1), and (Lewis x ODS)F sub(1) hybrids of male rats. Rats were given 0.05% BBN in their drinking water for 4 weeks and then a basal diet with or without a 5% Na-AsA supplement for 32 weeks. In urine of all F sub(1) hybrids, Na-AsA elevated pH and concentrations of sodium ion and total ascorbic acid. There were not significant differences for susceptibilities to BBN alone among the four F sub(1) hybrids. In all F sub(1) hybrids, administration of Na-AsA increased urinary bladder carcinogenesis when compared to the matched control rats given BBN alone. Susceptibilities to Na-AsA promotion were high in (F344 x WS)F sub(1) and (F344 x ODS)F sub(1) hybrids, whereas they were mild in (Lewis x WS)F sub(1) and (Lewis x ODS)F sub(1) hybrids. The present results therefore indicate that F sub(1) hybrids among the F344, ODS, Lewis and WS strains may be a useful model for analyzing host genes susceptible to Na-AsA promotion in rat bladder carcinogenesis.