The hypolipidemic effects of ethyl all-cis-5, 8, 11, 14, 17-icosapentaenoate (EPA-E) on cholesterol diet-fed rabbits were studied. EPA-E (300mg/kg, p.o.×4 weeks) decreased total cholesterols in the lipoprotein fractions of very lowdensity lipoprotein and intermediate lipoprotein+low-density lipoprotein (LDL), but not in high-density lipoprotein. Furthermore, the properties of LDL were investigated in rabbits given EPA-E (300mg/kg, p.o.×2 weeks). EPA-E had no influence on the lipid composition in LDL, and the cholesterol accumulation into macrophages was not increased by the incubation with EPA-E-treated LDL. However, the ω3 polyunsaturated fatty acids contents of LDL were increased by the administration of EPA-E. EPA-E-treated LDL was also studied on the binding to the hepatic membranes. The binding of EPA-E-treated LDL to the hepatic membranes was higher than that of ordinary LDL. These results suggest that EPA-E causes a modification of LDL, such that EPA-E has an enhancing effect on the hepatic uptake of LDL. These effects may contribute to the hypolipidemic action of EPA-E.
