In simple terms, how does blood clot and what substances are involved?

1 Answer
Dec 7, 2016

The immediate process of stopping bleeding after injury is known as hemostasis.


Blood clotting is a process that converts specific circulating elements of the blood system into a gel with insoluble characteristics. This prevents loss of blood from injured blood vessels, tissues or organs.

Injury to blood vessels which leads to platelet adhesion is the first step in blood clotting.
When platelets are activated, they activate the protein kinase and result in platelet aggregation.
The kallikrein - kinin protein complex initiates the blood coagulation cascade.

Prothrombin is activated to thrombin, which plays an important role in blood coagulation regulation.
Specific thrombin inhibitors control excess thrombin, as otherwise it would lead to release of fibrin peptides. This leads to formation of cross links on the surface of the damaged blood vessel.

The dissolution of the fibrin clot is the role of plasma and leads to the digestion of fibrin.