Stolselvorming

Stolselvorming, also known as clot formation or coagulation, is a crucial biological process that prevents excessive bleeding when a blood vessel is injured. This complex cascade involves a series of protein interactions, primarily within the blood plasma, that ultimately lead to the formation of a stable fibrin clot. The process begins with the activation of platelets, small cell fragments that aggregate at the site of injury. Simultaneously, a cascade of clotting factors, designated by Roman numerals, is initiated. These factors are enzymes that sequentially activate each other, amplifying the response. The intrinsic and extrinsic pathways of coagulation converge on a common pathway, where the production of thrombin is paramount. Thrombin then cleaves fibrinogen, a soluble plasma protein, into fibrin monomers. These monomers spontaneously polymerize to form a mesh-like network that traps blood cells and platelets, solidifying the clot. The final stages involve the cross-linking of this fibrin mesh by factor XIII, which strengthens the clot and stabilizes it. This intricate system ensures that bleeding is effectively stopped while allowing for the eventual repair of the injured vessel. Disorders of stolselvorming can lead to either excessive bleeding (hemorrhage) or unwanted clot formation within blood vessels (thrombosis).