Plasmin exposure modulates platelet aggregation responses, but a direct effect of plasmin on the platelet fibrinogen receptor, glycoprotein IIb/IIIa (GPIIb/IIIa), has never been conclusively shown in a plasma milieu. To examine this issue, we incubated platelets in platelet-rich plasma with plasmin and measured the effect of this treatment on platelet aggregation, fibrinogen binding, and the st...

Whereas bleeding is the most frequent adverse event encountered in patients receiving glycoprotein (GP) IIb/IIIa inhibitors, there are currently no recommendations for how to treat such patients. The present study tested the hypothesis that infusion of desmopressin (DDAVP) reverses the in vitro platelet dysfunction induced by GPIIb/IIIa inhibitors ( L-aspirin). Study group 1 (10 healthy volunte...

while platelet aggregation returned to baseline after 7 to 8 weeks (5). We also demonstrated a progressive reduction in platelet sensitivity to aspirin in longterm aspirin-treated patients. The genomic response to a pharmacological “challenge” with aspirin has also been demonstrated. After aspirin administration, a set of platelet-enriched genes and proteins associated with platelet function an...

BACKGROUND Diabetes mellitus is a major risk factor for adverse outcomes after acute coronary syndromes (ACS). Because this disease may be associated with increased platelet aggregation, we investigated whether diabetic patients with ACS derive particular benefit from platelet glycoprotein (GP) IIb/IIIa receptor inhibition. METHODS AND RESULTS We performed a meta-analysis of the diabetic popu...

For the long-term prevention of thromboembolic events in patients with atherosclerotic vascular disease, aspirin is the preferred antiplatelet drug. Only clopidogrel was shown to be more effective and at least as safe than medium-dose aspirin in direct comparative large-scale trials. Aspirin inhibits the cyclooxygenase dependent pathway of platelet aggregation while ticlopidine and clopidogrel ...

During the last decade, intensive efforts have been made to evaluate the role of the platelet glycoprotein (GP) IIb/IIIa complex in platelet-mediated thrombus formation. Significant efforts have also been made to design potent antagonists of this "final common pathway" of platelet aggregation to be used as novel therapeutic strategies to treat acute coronary syndromes. Although several differen...

Intravenous immunoglobulin (IVIgG) causes an acute rise in the platelet count in the majority of patients with chronic immune thrombocytopenic purpura (ITP) but the mechanism(s) of action is still unknown. We evaluated the ability of three different IVIgG preparations to inhibit the in vitro binding of autoantibody to platelet glycoprotein (GP) IIb/IIIa. ITP plasma, known to contain anti-GPIIb/...

891 I 1949, Ackroyd reported the abrupt onset of severe thrombocytopenia and purpura in patients receiving the sedative allylisopropylacetylcarbamide (Sedormid).1 All the patients had taken Sedormid previously and had become sensitized to it. Today, this classic picture of drug-induced, immunemediated thrombocytopenia is most often caused by quinine in outpatients and by vancomycin in hospitali...

We developed a monoclonal antibody, 1C1E7, against vWf that increases ristocetin-induced platelet aggregation in a dose-dependent manner and lowers the threshold concentration of ristocetin needed to obtain a full aggregatory response. The platelet aggregatory effect of asialo vWf (ASvWf) also is enhanced by 1C1E7, in the presence or absence of glycoprotein (GP) IIb/IIIa receptor antagonism. In...

Protein disulfide isomerase (PDI) present at platelet surfaces has been considered to play an important role in the conformational change and activation of the integrin glycoprotein IIb/IIIa (GPIIb/IIIa) and thus enhances platelet aggregation. Growing evidences indicated that platelet surface PDI may serve as a potential target for developing of a new class of antithrombotic agents. In the pres...