Epithelial cell proliferation in diverse models of experimental cholelithiasis.

Proliferation of the epithelial cells of the gall bladder during the initial stages of experimental cholelithiasis has been studied by autoradiography. Rabbits taking a diet with 1% dihydrocholesterol added showed a rise in labelling index from 1.5%-19% by three days. Mice taking a 1% cholesterol 0.5% cholic acid diet showed a similar rise from less than 1% to 15-21% at two and five days. Guinea-pigs receiving lincomycin showed a rise from less than 1% to 6% after 24 hours. These changes, which appear well before the appearance of gall stones, together with previous reports of enhanced mucous secretion during lithogenesis, make it clear that in these laboratory models of cholelithiasis the gall bladder is abnormal well before stones form.