The role of leucocytes in the acetyl salicylic acid (aspirin) induced nitric oxide synthesis in the production of interferon-α, a potent inhibitor of platelet aggregation and a thrombolytic agent

The role of aspirin-induced NO synthesis in the production of interferon-alpha (IFN-alpha) in leucocytes and the effect of IFN-alpha on platelet aggregation was studied. Treatment of Platelet Rich Plasma (PRP) with the dialyzed supernatant from the leucocyte suspension incubated with 80 mu M aspirin resulted in parallel syntheses of NO and IFN-alpha as determined by methemoglobin assay and enzyme linked immunosorbent assay respectively. Incubation of PRP with 10 nM purified IFN-alpha for 40 min resulted in the maximal inhibition of platelet aggregation through the synthesis of NO due to the activation of nitric oxide synthase in platelets by IFN-alpha. The treatment of clotted PRP with IFN-alpha resulted in the lysis of the clot due to the fibrinolysis. Injection of IFN-alpha was found to protect mice from death due to the lysis of ADP-induced coronary thrombus. Interferon-alpha was found to be a potent inhibitor of platelet aggregation and a thromboprotective agent.