Time Dependence of Whole Blood Aggregation in Response to Platelet Activating Factor (PAF)

Summary

The aggregation/adhesion response to platelet activating factor (PAF) was studied in diluted whole blood by impedance aggregometry. The extent of aggregation varied directly with the interval between blood sampling and aggregation measurement over the first 30 minutes from sampling, then remained stable for the next 60 minutes of observation. This is an effect opposite to that described for aggregation to PAF in platelet rich plasma which, however, cannot be studied soon after sampling. Time dependence of aggregation is important and comparative measurements should be made during the period of stable aggregability.

Keywords

Platelet aggregation - Platelet activating factor

• References

• 1 McManus LM, Hanahan DJ, Pinckard RN. Human platelet stimulation by acetyl glyceryl ether phosphorylcholine. J Clin Invest 1981; 67: 903-906
• 2 Kloprogge E, de Haas GH, Gorter G, Akkerman JW N. Properties of PAF-acether-induced platelet aggregation and secretion. Studies in gel-filtered human platelets Thromb Res 1983; 29: 595-608
• 3 Lecrubier C, Conard J, Horellou MH, Samama M. Study of platelet aggregation induced by platelet activating factor (PAF) after administration of ticlopidine or aspirin. Agents actions 1983; 13: 77-80
• 4 Fouque F, Vargaftig BB. Triggering by Paf-acether and adrenaline of cyclo-oxygenase-independent platelet aggregation. Br J Pharmac 1984; 83: 625-633
• 5 Russell-Smith NC, Flower RJ, Cardinal DC. Measuring platelet and leucocyte aggregation/adhesion responses in very small volumes of whole blood. J Pharmacol Meth 1981; 6: 315-333
• 6 Riess H, Braun G, Brehm G, Hiller E. Critical evaluation of platelet aggregation in whole human blood. Am J Clin Pathol 1986; 85: 50-56
• 7 Abbate R, Favilla S, Boddi M, Costanzo G, Prisco D. Factors influencing platelet aggregation in whole blood. Am J Clin Pathol 1986; 86: 91-96
• 8 Taylor RR, Sturm M, Vandongen R, Strophair J, Beilin LJ. Whole blood platelet aggregation is not affected by cigarette smoking but is sex related. Clin Exp Pharmacol Physiol 1987; 665-671
• 9 Kloprogge E, Hasselaar P, Gorter G, Akkerman JW N. Stimulus-aggregation coupling in platelets activated with PAF-axcether. Biochim Biophys Acta 1986; 883: 127-137
• 10 Bevan J, Heptinstall S, Knox A, Vathenen AS, Tattersfield AE. PAF-induced platelet aggregation in whole blood and the effect of administering BN52063 to man (Abstract). In: The role of plateletactivating factor in the immune response. Fondation IPSEN pour la Recherche Therapeutique; Paris: 1987