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Updated: Dec 20, 2025
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Comprehensive Analysis of Procoagulant Platelets Exhibiting Features of Necrosis, Apoptosis and Platelet Activation
Published on: May 23, 2025
936
Human platelets express functional ectonucleotidases that restrict platelet activation signaling.
Susheel N Chaurasia1, Geeta Kushwaha1, Abhishek Pandey2
1Department of Biochemistry, Institute of Medical Sciences, Banaras Hindu University, Varanasi, 221005, India.
Biochemical and Biophysical Research Communications
|May 25, 2020
Summary
Platelet ectonucleotidases CD39 and CD73 regulate extracellular nucleotides. Thrombin stimulation increases their activity, and CD73 inhibition enhances platelet signaling via calcium and protein phosphorylation.
Area of Science:
- Biochemistry
- Hematology
- Cell Biology
Background:
- Platelets are crucial for thrombosis and hemostasis.
- Platelets release adenine nucleotides upon stimulation.
- Ectonucleotidases, including CD39 and CD73, control extracellular nucleotide levels on platelet surfaces.
Purpose of the Study:
- To investigate the role of platelet ectonucleotidases CD39 and CD73 in platelet activation.
- To determine the effect of thrombin stimulation on ectonucleotidase expression and activity.
- To elucidate the impact of CD73 inhibition on thrombin-mediated platelet signaling.
Main Methods:
- Platelet stimulation with thrombin.
- Measurement of ectonucleotidase expression and enzymatic activity.
- Inhibition of CD73 activity.
- Assessment of protein tyrosine phosphorylation.
- Measurement of intracellular free calcium ([Ca2+]i).
Main Results:
- Thrombin stimulation significantly increased surface expression and activity of platelet ectonucleotidases CD39 and CD73.
- Inhibition of CD73 in thrombin-stimulated platelets resulted in enhanced protein tyrosine phosphorylation.
- CD73 inhibition also led to an increase in intracellular free calcium ([Ca2+]i) in thrombin-treated platelets.
Conclusions:
- Platelet ectonucleotidases CD39 and CD73 expression and activity are upregulated by thrombin.
- CD73 plays an inhibitory role in agonist-mediated platelet signaling.
- Inhibition of CD73 potentiates key signaling pathways, including calcium mobilization and protein phosphorylation, in activated platelets.
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