Effect of 3,4-dihydroxyacetophenone on rabbit platelet function

Platelet aggregation and serotonin release reaction were measured by recording light transmission and determining[14C] serotonin released from the labeled platelets respectively. 3,4-Dihydroxyacetophenone (DHAP) inhibited rabbit platelet aggregation both in vitro and in vivo. The ID50 of DHAP in inhibiting platelet aggregation in vitro were 6.3, 52 and 460 μg/ml, induced by arachidonic acid (AA), collagen and ADP respectively. DHAP also inhibited platelet [14C] serotonin release and heparin neutralizing activity induced by collagen and AA in a dose-dependent manner. In addition, DHAP showed an additive effect with PGE1 in inhibiting platelet aggregation and increasing platelet cAMP. Increasing platelet cAMP is likely the mechanism of inhibition of platelet function by DHAP.