Effects of sodium cyclamate and sodium saccharin on focus induction in explant cultures of rat bladder

✍ Scribed by Linda J. Nicholson; Harsha Jani

• Publisher: John Wiley and Sons
• Year: 1988
• Tongue: French
• Weight: 488 KB
• Volume: 42
• Category: Article
• ISSN: 0020-7136
• DOI: 10.1002/ijc.2910420226

✦ Synopsis

The tumour-promoting activities of sodium cyclamate and was assessed only in cultures treated with high doses of MNU sodium saccharin were investigated in an assay based on the which alone induced many foci, and although the promoting induction of epithelial foci exhibiting enhanced growth poten-activity of saccharin was demonstrated in cultures treated with tial in a rat bladder explant culture system. An initiating, non-a sub-threshold dose of MNU, a more accurate assessment of N-nitrosourea (MNU) to make promotion studies possible' the system. Furthermore, the apparent focus-inducing activity Saccharin induced epithelial foci when added to cultures pretreated with an initiating dose of MNU, and also the of cyclamate in the absence of previous initiation by carcinoincidence of foci in cultures treated with transforming doses gen m?eded confirmation, Particularly in view of the renewed of MNU. Cyclamate was found to induce a high incidence of interest in this compound.

foci when added to cultures by itself. When MNU and CY-

The present studies were carried out to extend and confirm clamate treatments were combined, an additive effect could the studies of ~~~~l~~ jani (1986) using an initiationbe detected. These results indicate that both cyclamate and promotion regime like those used in ,,iv0 (Hicks and Chowaniec, 1977; Hicks et a l . , 1975 Hicks et a l . , , 1978)).

saccharin can contribute to epithelial transformation in this system.

focusinducing dose was defined for the carcinogen N-methyl-sub-threshold doses of MNU was clearly needed to optimize 'To whom reprint requests should be addressed.