PIGMENT CHOLELITHIASIS INDUCED BY VITAMIN-A AND ITS PREVENTION BY BUTYLATED HYDROXYTOLUENE

We previously reported on the induction by vitamin A of gallstones, ri ch in calcium and phosphate, in hamsters. On the other hand, it has be en reported that the phenolic antioxidant butylated hydroxytoluene (BH T) potentiates the hepatotoxicity of vitamin A, In the present work we have tested the effect of BHT on the lithogenicity of vitamin A and o n bile composition, The urinary excretion of calcium and phosphate was determined to assess a possible asymptomatic bone resorption due to v itamin A toxicity, and/or an effect of BHT on the homeostasis of calci um and phosphate. Three groups of 18 male hamsters were fed with the f ollowing diets for 70 days: Group 1, Purina Nutricubes (DB); Group 2, DB + 25,000 IU% retinol acetate (DL); Group 3, DL + 500 mg% BHT. Vitam in A (Group 2) induced gallstones in 78% of the animals, increased bil e flow and biliary phosphate and calcium concentrations, and reduced t hose of bile salt, cholesterol and phospholipid, BHT (Group 3) reduced gallstone frequency to 5.5%, and decreased biliary phosphate, calcium and lipids toward more normal concentrations, Vitamin A alone or with BHT did not significantly affect food intake or urinary excretion of calcium and phosphate.