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Platelet-platelet recognition during aggregation: distinct mechanisms determined by the release reaction
Thrombosis and Haemostasis
|April 30, 1984
Summary
Fixed platelets with bound fibrinogen passively aid platelet aggregation, but only when specific compounds are released. This release mechanism is crucial for the interaction, enhancing aggregation at higher ADP concentrations.
Area of Science:
- Hematology
- Biochemistry
- Cell Biology
Background:
- Fixed platelets with bound fibrinogen passively participate in aggregation.
- Bound fibrinogen is essential for this platelet interaction.
Purpose of the Study:
- To investigate the role of the platelet release reaction in controlling passive aggregation.
- To understand how released compounds influence fixed platelet participation.
Main Methods:
- Examining aggregation of fresh platelets with fixed platelets at varying ADP concentrations.
- Assessing aggregation of aspirin-treated platelets and the effect of platelet supernatant.
- Investigating soluble fibrinogen binding and fixed platelet interaction with fresh platelets.
Main Results:
- Fixed platelets augmented aggregation at higher ADP concentrations (greater than 2 microM).
- Augmentation was lost in aspirin-treated platelets but restored by activated platelet supernatant.
- Interaction of fixed platelets with fresh platelets required the release reaction.
Conclusions:
- Fibrinogen covalently bound to fixed platelets is recognized by released platelet compounds.
- The platelet release reaction is critical for the functional interaction of fixed platelets in aggregation.
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