Influence of Bile Acids on the Synthesis of Biliary Phospholipids in Man

: The effect of interrupting the enterohepatic circulation (EHC) of bile acids on the synthesis of biliary lecithin in the human liver was studied. —- Carbon-14 palmitic acid was given intravenously to eight patients undergoing biliary drainage after cholecystectomy for uncomplicated gallstones, and the incorporation of label into biliary lecithin was determined. During intact EHC of bile acids the specific activity of biliary lecithin, after an initial peak, decreased progressively between 2–24 h after administration of label. During interrupted EHC the specific activity 5–6 h after the administration of label became stable at a plateau which persisted for at least 24 h. Duodenal feeding of bile acids during this period of stabilization resulted in a rapid and marked decrease in this activity. —- It is concluded that the bile acids in the EHC are a determining factor for the synthesis rate of biliary lecithin in the human liver. However, the mechanism for this effect on the lecithin synthesis cannot be clarified by this study.