THE EARLY PHASE OF COLON TUMORIGENESIS INDUCED BY DIMETHYLHYDRAZINE IN ICR MICE

In order to study the influence of fiber supplements on dimethylhydraz ine induction of colon tumorigenesis six-week-old CD1 (ICR): Crj mice were injected i.m. at a dimethylhydrazine (DMH) dose 10 mg/kg body wei ght once weekly for 10 weeks with or without dietary supplementation w ith 3% polydextrose, lactosucrose or cellulose, or 3% polydextrose and 3% cellulose in combination. There were no significant differences in colon tumor induction among the groups. However, microadenomas were o bserved 10 weeks after the first treatment of DMH so that this protoco l may be useful for studies of the early phase of colon carcinogenesis mice.