Biliary control of beta-glucuronidase activity in the luminal contents of the rat ileum, cecum, and rectum.

The effect of bile exclusion on intestinal beta-glucuronidase activity was studied in the rat. Bile exclusion dramatically decreased the bacterial beta-glucuronidase activity in the cecum and rectum but did not affect the normal low level in the ileum. Thus, bile flow may be the most important factor in modulating beta-glucuronidase activity in the rat large bowel. Dietary substances which can alter bile flow may thus have effects on intestinal bacterial beta-glucuronidase activity. Effects of diet on colon cancer might therefore be explicable in terms of altered bile flow rather than altered bacterial beta-glucuronidase induction.