a series of indole-based aryl(aroyl)hydrazone analogs of antiplatelet indole-3-carboxaldehyde phenylhydrazone were synthesized by the schiff base formation reaction and their antiplatelet activity was assessed using human platelet rich plasma. the platelet concentrate was obtained using a two-step centrifugation protocol and adp, arachidonic acid and collagen were used as inducers of platelet a...

Actions Dipyridamole, the active ingredient of PERSANTIN, inhibits the uptake of adenosine into the erythrocytes, platelets and endothelial cells in vitro and in vivo; the inhibition amounts to 80% at its maximum and occurs dose-dependently at therapeutic concentrations (0.5 2 mcg/ml). Consequently, there is an increased concentration of adenosine locally at the platelet A2-receptor, stimulatin...

OBJECTIVE Several platelet proteins are palmitoylated, but whether protein palmitoylation functions in platelet activation is unknown. We sought to determine the role of platelet protein palmitoylation in platelet activation and thrombus formation. METHODS AND RESULTS Platelet proteins were depalmitoylated by infusing acyl-protein thioesterase 1 into permeabilized platelets. In intact platele...

Aspirin, as an inhibitor of platelet aggregation, may be of benefit in ischemic heart disease. However, aspirin blocks not only platelet aggregation but also synthesis of prostacyclin, a vasodilator and platelet deaggregator. The relative sensitivity of prostaglandin-mediated coronary vasodilatation and platelet aggregation to inhibition by aspirin remains uncertain. We therefore investigated t...

Aggregometry studies on endotoxic lipopolysaccharide (LPS) -mediated rabbit platelet aggregation were performed. Different preparations of LPS showed characteristic aggregometry profiles, and LPS with potent anticomplementary activities generally had a more vigorous platelet aggregation function than did LPS preparations with lesser anticomplementa ry functions. Cobra venom a nticomplementary f...

The interaction between platelet glycoprotein Ib and von Willebrand factor (vWF) plays a crucial role in platelet-mediated thrombus formation under high-shear-stress conditions. The aim of this study was to investigate the antiplatelet profile of a humanized anti-vWF monoclonal antibody, AJW200. In vitro studies were performed with a modified cone-and-plate viscometer and human platelets. AJW20...

Inhibition of the P2Y12 pathway by the platelet antagonist clopidogrel is associated with a marked reduction in platelet reactivity. Recent reports have shown that P2Y12 inhibition has anti-inflammatory effects as well. However, whether clopidogrel withdrawal is associated with proaggregatory and proinflammatory effects has not yet been explored. Since diabetic subjects are characterized by a p...

The effects of lysolecithin (LPC) on aggregation, serotonin release, shape, and lysis of rabbit, pig, or human platelets in platelet-rich plasma (PRP) or Tyrode albumin solution were examined during prolonged incubation. LPC added to citrated or heparinized PRP from humans or rabbits at a final concentration above 100 muM caused instantaneous inhibition of platelet aggregation induced by adenos...

A platelet aggregation inhibitory protein, bitistatin, was isolated from the venom of the puff adder Bitis arietans. This protein is a single-chain peptide containing 83 amino acids and 7 disulfide bonds. Bitistatin contains the sequence arginine-glycine-aspartic acid and shows considerable homology to two previously described snake venom platelet aggregation inhibitors, trigramin and echistati...

The effects of lysolecithin (LPC) on aggregation, serotonin release, shape, and lysis of rabbit, pig, or human platelets in platelet-rich plasma (PRP) or Tyrode albumin solution were examined during prolonged incubation. LPC added to citrated or heparinized PRP from humans or rabbits at a final concentration above 100 uM caused instantaneous inhibition of platelet aggregation induced by adenosi...