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Characterizing Modulators of Protease-Activated Receptors with a Calcium Mobilization Assay Using a Plate Reader
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Protease activated receptors 1 and 4 govern the responses of human platelets to thrombin

Frederick A Ofosu1

  • 1Department of Pathology and Molecular Medicine, Faculty of Health Sciences, McMaster University, 1200 Main Street West, 3N26, Hamilton, Ont., Canada L8N 3Z5. ofosuf@mcmaster.ca

Transfusion and Apheresis Science : Official Journal of the World Apheresis Association : Official Journal of the European Society for Haemapheresis
|May 3, 2003
PubMed

Studies carried out in the past 12 years have established that activation of protease-activated receptor (PAR)-1 and PAR-4 by thrombin essentially drives human platelet activation. Thrombin is the most potent physiologic agonist of platelets. PAR-1 and PAR-4 are found on human platelets and are half of the family of the four known 7-transmembrane receptors that are activated by a single proteolytic cleavage within the amino terminal extracellular domain of these receptors. This review will consider the direct and indirect evidence that apparently support the idea that PAR-1 and PAR-4 activation by thrombin drives platelet activation

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