EFFECT OF THE INHIBITORS OF DIFFERENT STEPS OF CHOLESTEROL-BIOSYNTHESIS PATHWAY ON HIGH-DENSITY-LIPOPROTEIN BINDING TO ISOLATED HUMAN ENTEROCYTES

The effect of cholesterol synthesis inhibitors on high-density lipopro tein (HDL3) binding to isolated human small intestine epithelial cells was studied. Lovastatin (2 nM), ketoconazole (1 muM), miconazole (2 m uM), compound U-18666A (1 mug/ml), 25-hydroxycholesterol (1 muM) and t aurocholic acid (2 mM) inhibited [C-14]acetate incorporation into chol esterol; lovastatin and ketoconazole also inhibited [C-14]oleic acid i ncorporation into cholesteryl esters. All inhibitors down-regulate HDL 3 binding to enterocytes; good correlation was observed between the ef fects of the compounds on cholesterol synthesis and HDL3 binding. Thes e data allow one to assume that newly synthesized cholesterol rather t han cholesterol biosynthesis pathway intermediates is a regulator of H DL receptors.