Examination of Platelet Function in Whole Blood Under Dynamic Flow Conditions With the Cone and Plate(let) Analyzer Effect of Erythrocytosis and Thrombocytosis

Department of Medicine, Cornell University, Итак, New York, United States
American Journal of Clinical Pathology (Impact Factor: 2.51). 04/2007; 127(3):422-8. DOI: 10.1309/B29E2AHMTQA1KAKJ
Source: PubMed


We studied cone and plate(let) analysis (CPA) for evaluating global platelet function in whole blood under arterial flow conditions (approximately 1,800 seconds(-1)). CPA allows direct visualization and quantitation of platelet adhesion (surface coverage [SC]) and determination of average aggregate size (AS) following brief shearing of a small blood sample (3.2% sodium citrate) in plastic wells. By using blood from healthy volunteers manipulated to alter platelet or RBC counts and blood from patients with myeloproliferative disorders (MPDs), quantitative and qualitative changes in SC and AS were observed. Thrombocytosis resulted in increased SC, whereas erythrocytosis increased AS. The RBC volume (mean corpuscular volume) had no effect. It is interesting that differences in CPA AS were discerned among subgroups of patients with MPD undergoing different treatment regimens. These studies suggest that CPA platelet deposition patterns may provide novel insight into global platelet function during hemodynamic flow.

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    • "Human blood was collected from healthy, medication-free donors in tri-sodium citrate 3.8%, 1:7 ratio. Platelet rich plasma (PRP) was prepared as before [30] with the following modifications. Briefly, blood was centrifuged at 800 rpm for 15 minutes, PRP collected and further centrifuged at 5000 rpm for 4 minutes in the presence of citrate (5 mM). "
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