COLONIC MUCOSAL PROLIFERATION AFTER PANCREATICOBILIARY DIVERSION IN THE HAMSTER

The effect of pancreaticobiliary diversion (PBD) on the colonic mucosa was studied in hamsters over 5, 10, and 24 days. Sham-operated animals served as controls. At all three time intervals, experimental animals had increased plasma cholecystokinin concentrations and decreased gastrin concentrations. Five days after PBD, there was an increase in scintigraphically measured [H-3]thymidine incorporation into colonic tissue. Correspondingly, there was an increase in the [H-3]thymidine DNA labeling index of goblet cells in the colonic mucosa. The total number of cells in the colonic crypt columns were significantly increased on days 5, 10 and 24. Whether this proliferative response in the colon is due to increased release of cholecystokinin, enteroglucagon, other aberrations of hormones or growth factors, or simply an increased bile load on the colonic mucosa remains to be clarified. Such further studies may reveal an alternative animal model for studies on risk factors in colonic carcinogenesis.