Summary
Morphologic observations of coagulation, clot maturation and fibrinolysis in thin
standardized clots were presented using negative and positive phase contrast microscopy.
The study described the beginning of fibrin formation in centers away from platelets
and platelet clumps but usually associated with platelet fragments. Although the preparations
failed to reveal clot retraction, the fibrin strands did show a change in refractive
index. Intact clot preparations were demonstrated several weeks after incubation at
37° 0.
The observation of greatest significance, in the light of recent studies accentuating
the role of platelets in hemostasis, was the lysis of platelets and platelet clumps
which had undergone viscous metamorphosis. This action of plasmin on platelets may
be of great importance in the prevention of hemostasis in the fibrinolytic syndrome
and the destruction of damaged platelets in the normal circulation.
