Effect of bile acids on formation of azoxymethane-induced aberrant crypt foci in colostomized F344 rat colon.

The effect of bile acids on the formation of azoxymethane induced aberrant crypt foci (ACF) was investigated using the fecal stream-excluded colons of colostomized F344 rats. The excluded colon was irrigated with saline or bile acids (1 mg/0.5 ml per day, 5 days/week) for 4 weeks. The mean numbers of ACF per colon in rats given cholic acid, deoxycholic acid (DCA), chenodeoxycholic acid (CDCA), lithocholic acid, and ursodeoxycholic acid (UDCA) were 160.8, 118.2, 227.8, 150.7 and 87.3, respectively, while that of the control was 174.0. The number of ACF was significantly larger in CDCA, but smaller in UDCA and DCA-treated rats than the control (P<0.01). DCA did not induce apoptosis in the colon under the present conditions.