RELATIONSHIP BETWEEN DIET AND GALLSTONES IN HAMSTERS

The present study aimed at the induction of cholesterol stones (Ch S) in young hamsters with a diet rich in refined carbohydrate and animal fats, and that of pigment stones (P S) in adult hamsters with a low protein diet. After four weeks of feeding according to the above-mentioned protocol, the rate of gallstone formation in the Ch S and P S groups were 81.56% and 89.77% respectively, while those of the control groups were 20% and 40% (P<0.001). Eight weeks after switching back to normal diet, the amount of gallstones in both experimental groups decreased significantly; in some animals, the stones disappeared completely. The ratio of cholesterol/bilirubin in stones of the Ch S group is three times that of the control group, and the same ratio in atones of the P S group is 47% that of the control. During the period of stone formation, the bile of the Ch S group was supersaturated with cholesterol, while unconjugated bilirubin increased significantly in the bile of the P S group. There was a general decline in different bile acids in bile of both groups. During the later period of stone dissolution, the bile components of both lithogenic groups tended to become normal, but glycocholic acid alone increased greatly. The result suggests that the type of diet is closely related to the formation and dissolution of gallstones. It has also been demonstrated that the lithogenic tendency of the bile can be reversed and gallstones dissolved in the early stage of their formation.