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THE VISCOUS METAMORPHOSIS OF THE BLOOD PLATELETS.
1Pathological Laboratory of the Massachusetts General Hospital, Boston.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Viscous metamorphosis of blood platelets during coagulation is linked to thrombin formation and calcium presence. This platelet change, crucial for coagulation, occurs similarly across various blood sources and is influenced by serum globulins.
Area of Science:
- Hematology
- Biochemistry
- Cell Biology
Background:
- Blood platelets undergo viscous metamorphosis during coagulation.
- This phenomenon is closely linked to the early stages of blood clotting.
- Calcium is identified as an important, though not essential, factor.
Purpose of the Study:
- To investigate the factors influencing viscous metamorphosis of blood platelets.
- To understand the relationship between platelet metamorphosis and blood coagulation.
- To identify the specific substances in serum responsible for this reaction.
Main Methods:
- Experimental analysis of blood platelets and coagulation factors.
- Testing various substances and mixtures for their ability to induce platelet metamorphosis.
- Fractionation of serum to isolate active components.
- Heat denaturation and barium sulfate absorption experiments.
Main Results:
- Viscous metamorphosis is associated with thrombin generation and calcium.
- Substances causing metamorphosis are linked to fibrinogen alteration or thrombin.
- Serum globulins, not albumins, contain the platelet-metamorphosing substance.
- This substance is heat-labile and shares properties with serozyme.
- Platelet agglutination is an integral part of viscous metamorphosis.
Conclusions:
- Viscous metamorphosis of platelets is a key event in early coagulation.
- Serozyme-like substances, particularly those related to thrombin and calcium, are primary drivers.
- The reaction is quantitative and influenced by the concentration of active factors.
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