Summary
Platelets collected with an EDTA solution and simply washed in an incomplete Tyrode’s presented clotting times in the recalcification (man and rat) and the Stypven (rat) tests that were practically identical to those of the PRP when slow speed centrifugation was used (800 G in man, 1000 G in rat). This was demonstrated, in 6 pools of 5 rats each and in 6 men, by comparing the clotting activity of the citrated platelet-rich plasma to that of the platelets washed and resuspended in the citrated platelet-poor plasma, for platelet counts ranging from 1 × 105 to 10 × 105/mm3. In contrast, centrifugation of platelets at 3000 G markedly affected these clotting activities, as was shown in an additional study comprising 6 pools of 3 rats.
Finally, the clotting activity of platelets totally disrupted by sonication appears to be identical quantitatively in both man and rats to that of the total phospholipids extracted from these platelets and separated from the other lipids by thin-layer chromatography and resuspended in plasma by sonication.