Human Platelets Have Cholesteryl Ester Hydrolytic Activity Toward Plasma High Density Lipoproteins

Human platelet cholesteryl ester hydrolytic (CEH) activity was determined toward high density lipoprotein (HDL) labelled with cholesteryl [1-14C] oleate resulting in esterilkation of [l-14C] oleate to platelet phospholipid. The observed CEH activity was enhanced by 100 nM prostacyclin (PGI2), inhibited by 500 μM 2′, 3′ dideoxyadenosine (DDA), but unaffected by 100 mM chloroquine diphosphate. The CEH activity may represent a mechanism for delivery of other unsaturated fatty acids from HDL to platelets with subsequent modification of the fatty acid composition of platelet phospholipids and potential modification of platelet reactivity.