ACTIVITY OF PLATELET IN PATIENTS WITH HIGH-LEVEL OF LDL AND THE EFFECT OF LDL ON PLATELET GLYCOPROTEINS

Objective To investigate the activity of platelet in patients with hig h level of low density lipoproteins (LDL and the effect of LDL on plat elet glycoproteins (GP). Methods Platelet glycoproteins, whose platele t were activated or unactivated, were measured by flow cytometry. Resu lts The amount of the platelet membrane GP II: b/III a in patients was not significantly different from that of the control when platelet wa s unactivated (P > 0.05); when platelet was activated by adenosine dip hosphate (ADP), the amount of patients' platelet GP II b/III a was inc reased markedly in comparison with that in the control (P < 0.01). Hav ing been preincubated with LDL, the platelets were activated by ADP an d the amounts of GP II b/IIIa of patients group and the control were a ll increased obviously as compared with those in the platelets which w ere not incubated with LDL (P < 0.01; P < 0.01). There was no signific ant difference of the amount of granule membrane protein-140 (GMP-140) between patients and the control when platelet was activated by throm bin (P > 0.05). Having been preincubated with LDL, platelet was activa ted by thrombin, the amounts of GMP-140 on patients' and control plate let were all increased markedly (P < 0.01, P < 0.01). Conclusion The a ctivity of platelet in patients with high level of LDL is increased si gnificantly. LDL can increase the expression of platelet glycoproteins .