EFFECTS OF GEMFIBROZIL ON PLASMA-LIPOPROTEINS, PLASMA ACTIVITIES OF HEPATIC-ENZYMES, AND HEMOSTATIC VARIABLES IN HYPERTRIGLYCERIDEMIC PATIENTS

In 15 patients with hypertriglyceridemia-defined as plasma triglycerid e (TG) concentration >250 mg/dL-gemfibrozil 600 mg given twice daily f or 4 months significantly reduced the mean plasma concentration of tot al cholesterol (TC) (-15%) and TG (-61%). In the low-density lipoprote in (LDL) fraction, the TC concentration was unchanged but the TG conce ntration was decreased. As the apoprotein B concentration also decreas ed, it is likely that the LDL particles were not only enriched with TC but also reduced in number. The increase in high-density lipoprotein cholesterol (HDL-C) was accounted for by an increase in the TC content of HDL(3). Most of these changes can be considered beneficial in term s of protection against atherosclerosis. The plasma activities of leci thin-cholesterol acyltransferase and hepatic lipase were not changed s ignificantly by the drug, while that of lipoprotein lipase increased s ignificantly (44.1%, P < 0.05). Thus the mechanism of action of gemfib rozil appears to mainly involve an increased catabolism of TG-rich lip oproteins, although the correlations between lipoprotein lipase and li poprotein concentrations were only marginally significant, As signific ant correlations were found between hepatic lipase and HDL-C, gemfibro zil appears to also have some impact on hepatic lipase. Finally, gemfi brozil did not change the activity of the fibrinolytic system, while t he fibrinogen concentration and the platelet count increased, The sign ificance of the latter changes is unclear.