Bile acids in the fetal rat: effect of maternal bile duct ligation.

The effect of bile duct ligation during pregnancy in rats (thereby increasing maternal plasma bile acids levels) on the bile acid content and composition in the fetus was examined. In spite of 30-fold increase in maternal plasma cholic acid, the bile acid content in the fetus of bile duct ligated rats was significantly lower (p less than 0.05) with a significant reduction in cholic acid content. Plasma cholesterol levels of fetuses from bile duct ligated rats were also significantly lower (p less than 0.05). In addition to the commonly expected bile acids, gas-liquid chromatographic analysis of the fetal bile acid pool showed peaks corresponding to several secondary bile acids. These results suggest that the transfer of primary bile acids of maternal origin into the fetus is minimal.