Cholesterol Solubilization by Solutions of Bile Salts and Bile Salts Plus Lecithin ∗

Abstract

Summary

Model synthetic solutions were used to study cholesterol solubilization by the 6 conjugated bile salts found in human bile individually and as a mixture, and by lecithin in combination with bile salts. In the range of concentrations found in bile, bile salts alone solubilized only about one third as much cholesterol as might be found in comparable concentrated human gallbladder bile. Between 0.023 and 0.046 mmoles of cholesterol were solubilized per mmole of bile salts. Addition of lecithin to a bile salt solution increased the quantity of cholesterol dissolved to values observed in bile; 0.36 mmoles of cholesterol was solubilized per mmole of added lecithin. Cholesterol solubilization by lecithin was independent of the concentration and nature of the bile salt.