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Turbidimetry on Human Washed Platelets: The Effect of the Pannexin1-inhibitor Brilliant Blue FCF on Collagen-induced Aggregation
Published on: April 6, 2017
Collagen/endogenous thrombin-induced platelet aggregation in whole blood samples
Gerhard Cvirn1, Siegfried Gallistl, Joerg Kutschera
1Institute of Physiological Chemistry, Medical University of Graz, Graz, Austria. gerhard.cvirn@meduni-graz.at
Summary
Endogenously generated thrombin potently activates platelets in whole blood. Combining thrombin with collagen significantly shortens the lag time for platelet aggregation, demonstrating a synergistic effect on this crucial early step.
Area of Science:
- Hematology
- Thrombosis Research
- Platelet Physiology
Background:
- Platelet aggregation is central to hemostasis and thrombosis.
- Understanding the roles of agonists like collagen and thrombin is critical.
- Investigating their effects in whole blood provides physiological relevance.
Purpose of the Study:
- To examine the individual and combined effects of collagen and endogenous thrombin on platelet aggregation.
- To assess these effects within the physiological context of whole blood.
- To determine potential synergistic interactions between these agonists.
Main Methods:
- Utilized the impedance method to measure platelet aggregation in whole blood.
- Stimulated aggregation using collagen (3.5 microg/ml) and endogenously generated thrombin (0.35 pmol/l tissue factor).
- Employed thrombelastometry to evaluate clot formation and thrombin potentials.
Main Results:
- Combination of collagen and endogenous thrombin significantly reduced lag times for platelet aggregation (41.9 s) compared to individual agonists (collagen: 173.8 s; thrombin: 94.3 s).
- Lowest amplitudes and slopes were observed with collagen alone, while thrombin effects were similar with or without collagen.
- No synergistic effect on clot formation or thrombin potential was detected via thrombelastometry.
Conclusions:
- Endogenously generated thrombin acts as a potent platelet agonist in whole blood.
- Collagen and endogenous thrombin exhibit a synergistic effect by significantly shortening the lag time to platelet aggregation onset.
- While synergistic on aggregation initiation, combined effects on overall clot dynamics were not observed.
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