Effect of L-tryptophan and sodium saccharin on urinary tract carcinogenesis initiated by N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide.
نویسندگان
چکیده
The effect of sodium saccharin (SAC) or L-tryptophan (LT) on urinary bladder carcinogenesis initiated by feeding N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANFT) for 4 weeks as 0.2% of the diet to male F344 weanling rats was evaluated. SAC was fed as 5% of the diet, and LT was 2% of the diet. FANFT fed for 4 weeks followed by 100 weeks of control diet did not produce any carcinomas; one of 25 rats developed a bladder papilloma. Of 26 rats fed SAC for 100 weeks after FANFT, two developed papillomas, and five developed carcinomas (p less than 0.03). Of 26 rats fed LT for 100 weeks after FANFT, three developed papillomas, and two developed carcinomas (p greater than 0.1) Eight rats fed FANFT for 72 weeks all developed bladder carcinomas, but rats fed control diet alone, control diet with SAC, or control diet with LT did not develop any bladder tumors. Scanning electron microscopic examination of Week 104 of the experiment showed the presence of pleomorphic microvilli on the bladder surface of some rats fed SAC of LT whether following 4 weeks of control diet alone or 4 weeks of FANFT. Four weeks of FANFT feeding, a lower dose than used previously in our studies, appears to be a subcarcinogenic level. Under these experimental conditions, the promoting activity of SAC is demonstrated with statistical significance. The results with LT were not statistically significant.
منابع مشابه
Effect of sodium phenobarbital and sodium saccharin in AIN-76A diet on carcinogenesis initiated with N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide and N,N-dibutylnitrosamine in male F344 rats.
Promoting activities of sodium phenobarbital (PB) and sodium saccharin (SS), incorporated in a semisynthetic diet (AIN-76A), on 2-stage carcinogenesis initiated with N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANFT) or N,N-dibutylnitrosamine (DBN) in male F344 rats were investigated. For the first 4 weeks of the experiment, weanling male Fischer rats were fed Wayne diet containing 0.2% FANFT...
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ورودعنوان ژورنال:
- Cancer research
دوره 41 8 شماره
صفحات -
تاریخ انتشار 1981