Related Experiment Video
Updated: Jan 10, 2026
04:37
Comprehensive Analysis of Procoagulant Platelets Exhibiting Features of Necrosis, Apoptosis and Platelet Activation
Published on: May 23, 2025
983
Thrombin-induced platelet secretion. Further evidence for a specific pathway
The Journal of Clinical Investigation
|June 1, 1979
Summary
Thrombin exposure can make human platelets less responsive to subsequent stimulation, a phenomenon specific to thrombin-induced serotonin secretion. This refractoriness occurs after thrombin binding but before adenylate cyclase regulation.
Area of Science:
- Hematology
- Biochemistry
- Cell Biology
Background:
- Platelet activation and secretion are crucial for hemostasis.
- Thrombin is a key mediator of platelet aggregation and secretion.
- Prostacyclin inhibits platelet secretion by increasing cyclic adenosine 3',5'-monophosphate (cAMP).
Purpose of the Study:
- To investigate the interaction between thrombin and human platelets.
- To determine the effect of prostacyclin on thrombin-induced platelet responses.
- To characterize the phenomenon of thrombin-induced platelet refractoriness.
Main Methods:
- Human platelets were treated with prostacyclin to increase cAMP levels.
- Platelets were briefly exposed to low concentrations of thrombin.
- Refractoriness to a second thrombin exposure was assessed by measuring serotonin secretion.
Main Results:
- Prostacyclin-treated platelets exposed to thrombin developed a diminished capacity for subsequent serotonin secretion.
- This refractoriness was thrombin-specific and concentration-dependent.
- The inhibition occurred downstream of thrombin binding and upstream of adenylate cyclase regulation.
Conclusions:
- Thrombin induces a specific refractoriness in human platelets affecting serotonin secretion.
- This suggests a signaling step between thrombin binding and cAMP regulation.
- This pathway transmits the signal for the extrusion of intracellular granular contents.
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