Library · Physiology
Fibrinolysis
Make it clearer
A clot is a temporary fix. When it is no longer needed, the body takes it apart, and that is called fibrinolysis: the dissolving of fibrin, the mesh that held the clot together.
The process starts with a couple of activators, tissue plasminogen activator and the urokinase-type activator. Both do the same thing: they switch on plasminogen, a component of the fibrinolytic system.
Once switched on, plasminogen becomes plasmin, and plasmin is the enzyme that dissolves the clot. It acts directly on the fibrin mesh and breaks it apart.
Think of scaffolding that comes down once the building is finished. That breakdown leaves pieces behind, the fibrin degradation products, and one of them is D-dimer. In the end most of them are cleared by proteases, which are enzymes that cut proteins, and by the mononuclear phagocyte system, the group of cells that eat up debris, mainly in the liver.
In brief
When the clot is no longer needed, tissue plasminogen activator and the urokinase-type activator activate plasminogen.
Scaffolding that comes down once the building is finished.
That activation produces plasmin, the enzyme that dissolves the clot and acts directly on the fibrin mesh, breaking it apart.
That breakdown yields fibrin degradation products, one of which is D-dimer.
Proteases and the mononuclear phagocyte system, mainly in the liver, clear most of these products.
Sources (2)
- National Center for Biotechnology Information, StatPearls PublishingD-Dimer Test, StatPearlsPublished
- National Center for Biotechnology Information, StatPearls PublishingPhysiology, Coagulation Pathways, StatPearlsPublished
This page explains the topic in general terms; it does not tell anyone what treatment to follow.
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