Comparative study of the effect of beta-blockers with different pharmacological properties on cholesteryl ester...

The effect of three beta-blockers: non-selective (propranolol), beta 1-selective (metoprolol), and with intrinsic sympathomimetic activity (pindolol), was investigated on 14C-oleic acid incorporation into cholesteryl esters in mouse peritoneal macrophages. Incorporation of 14C-oleic acid into cholesteryl esters was reduced about 10-fold by propranolol at 10(-4) M while incorporation into triacylglycerols was only 30% decreased at the same concentration. Metoprolol and pindolol had no significant effect on 14C-oleic incorporation into cholesteryl esters or triacylglycerols. Finally, propranolol inhibited the acyl-coenzyme A: cholesterol-O-acyltransferase activity, measured in vitro on macrophages homogenates, while the other studied beta-blockers were ineffective. These results suggest that propranolol could antagonize cholesteryl ester accumulation by macrophages, one of the main processes involved in atherogenesis.