Effect of diabetes and of 7 alpha-hydroxycholesterol infusion on the profile of bile acids secreted by the isolated rat livers.

The isolated livers from normal, streptozotocin-diabetic, and insulin-treated diabetic rats were perfused without and with infused 7 alpha-hydroxycholesterol. Biliary bile acids were extracted and analysed by gas chromatography. In each liver group, total bile acid concentration was more than four times greater with infused 7 alpha-hydroxycholesterol than without the sterol. Without infused 7 alpha-hydroxycholesterol, bile acids in the control group were composed mainly of beta-muricholic acid and to a lesser extent of cholic acid. In the diabetic group, the ratio between these two bile acids reversed. The ratio tended to be normalized by treatment with insulin. With infused 7 alpha-hydroxycholesterol, the control group secreted chenodeoxycholic acid at a considerable higher percentage besides major beta-muricholic acid and minor cholic acid. In the diabetic group, the ratio between the latter two bile acids reversed as was the case with the endogenous secretion, while the percentage of chenodeoxycholic acid remained then unchanged. The diminished percentage of beta-muricholic acid in the diabetic group was increased two times by treatment with insulin.