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Procoagulant Platelet Characterization by Measuring Phosphatidylserine Exposure and Microvesicle Release from Human Purified Platelets
Published on: November 29, 2024
Platelet energetic enzymes
Revue Roumaine De Medecine Interne (1964)
|January 1, 1975
Summary
Human and rabbit platelets show distinct lactate dehydrogenase (LDH) isoenzyme patterns. Magnesium-activated adenosine triphosphatase (ATP-ase) was found to be dominant in human platelet cytolysates.
Area of Science:
- Biochemistry
- Hematology
Background:
- Platelets play crucial roles in hemostasis and thrombosis.
- Lactate dehydrogenase (LDH) and adenosine triphosphatase (ATP-ase) are key enzymes involved in cellular metabolism and function.
Purpose of the Study:
- To investigate the isoenzymic patterns of LDH in human and rabbit platelets.
- To determine the activity of Mg++ and Ca++ activated ATP-ase in human platelets.
Main Methods:
- Analysis of LDH isoenzymes using zymography in platelet cytolysates.
- Assay of Mg++ and Ca++ activated ATP-ase activity in human platelet cytolysates.
Main Results:
- Human platelet LDH zymograms exhibited an intermediary pattern with 4 or 5 fractions, and a H/M subunit ratio above 1.
- Rabbit platelet LDH zymograms showed an anodal pattern with 4 bands, similar H/M subunit ratio variations as humans.
- Magnesium-activated ATP-ase was the predominant form in human platelet cytolysates.
Conclusions:
- Distinct LDH isoenzymic profiles exist between human and rabbit platelets.
- Mg++ activated ATP-ase is the dominant form in human platelets, suggesting its significant role in platelet function.
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