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Updated: Aug 7, 2026

Characterizing Modulators of Protease-Activated Receptors with a Calcium Mobilization Assay Using a Plate Reader
Published on: May 24, 2024
Pathophysiology of platelet thrombin receptors
1American Red Cross, Rockville, MD 20855, USA. Jamieson@USA.redcross.org
Abstract:
The evidence is reviewed and a model presented for two distinct receptors being involved in platelet activation induced by alpha-thrombin: a high affinity thrombin receptor constituting approximately 50 copies of a supercomplexed form of GPIb coupled to phospholipase A2 and a moderate affinity receptor constituting approximately 2000 copies of the proteolytically activated, G protein-coupled seven transmembrane domain receptor coupled to phospholipase C. Reasons for the failure of certain studies to detect this role for GPIb are discussed.
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