Effects of soluble fraction of porcine tissue on the aggregation of human blood platelets.

Epistaxis has been controlled by the use of porcine strip packing in patients with thrombocytopenia prior to and with platelet transfusion. The present study has extended previous observations about the probable mode of action of porcine tissue, to show that the addition of an aqueous fraction (AF) of homogenized porcine tissue to platelets causes prompt aggregation in vitro. Human platelet rich plasma was aggregated by the AF using standard turbidimetric techniques. AF acted synergistically with nonaggregating amounts of either adenosine diphosphate or collagen to cause aggregation. Platelet aggregation was enhanced by AF both with 300,000 platelets/cu mm (standard) or with reduced platelet numbers (50,000/cu mm). The results further define possible mechanisms of action of porcine strip packing in patients who have epistaxis and are thrombocytopenic.