Effects of VLDL, chylomicrons, and chylomicron remnants on platelet aggregability.

Although influences of cholesterol-rich lipoproteins on platelet aggregation are well established, the knowledge of interactions between triglyceride-rich lipoproteins and platelets, in particular in the postprandial state, is limited and controversial. The in-vitro effects of these lipoproteins from hypertriglyceridemic subjects on the aggregation behavior of platelets from normolipemic donors were investigated with two whole-blood methods. VLDL and chylomicrons, but not chylomicron remnants, in concentrations comparable to concentrations occurring after a fatty meal, reduced platelet aggregation in a dose-dependent manner in particle counting. Impedance aggregometry failed to monitor these effects. We conclude, that triglyceride-rich lipoproteins inhibit platelet aggregation in vitro. They may, therefore, not be linked to the acute onset of myocardial infarction.