The effects of cholestyramine on high density lipoprotein metabolism

Abstract

This study on 4 type II hyperlipoproteinaemic subjects examines the effects of pharmacologic doses (8 g twice daily) of the bile acid sequestrant cholestyramine on the plasma distribution and chemical composition of the high density lipoprotein subfractions, HDL 2 and HDL 3, and describes the influence of the drug on the metabolism of the major HDL apoproteins, apolipoprotein A-I and A-II. Cholestyramine lowered plasma low density lipoprotein cholesterol (32%; P < 0.05) without affecting the level of that lipid in very low density or high density lipoproteins. However, the plasma HDL 2 HDL 3 ratio and apolipoprotein A-I concentration rose significantly on treatment, while apolipoprotein A-II remained unchanged. The rise in apolipoprotein A-I derived from an increase in its synthetic rate and produced a relative enrichment of the protein with respect to apolipoprotein A-II in both HDL subfractions. These results demonstrate the cholestyramine treatment affects HDL metabolism in a way which, according to current concepts, may prove beneficial to the recipient.