Kininogen

TK is believed to be a biological indicator of senescence in rats,[1] which can be measured by the level of endothelial cell production during the aging process.

[8] HK and LK are created by the alternative splicing of the same kininogen (KNG) gene, which in humans, is located at chromosome 3q27.

[11] Factor XII is a zymogen, and upon binding with tissue to the anionic surface, exhibits some protease activity, starting the enzymatic cascade.

In the kinin-kallikrein system, the proteolytic cleavage of HK by the enzyme plasma kallikrein makes bradykinin, an inflammatory mediator that can lower blood pressure by way of vasodilation.

KNG is believed to play a role in the formation of thrombi, or blood clots that obstruct a vessel, and in inflammation.

The inhibition of KNG is potentially a selective strategy to fight stroke, deep vein thrombosis (DVT),[17] and other venous thromboembolic diseases.

Protein structure of bradykinin. Bradykinin is a nine amino acid-long polypeptide made by the cleavage of high-molecular-weight kininogen at D4. It acts as an inflammatory mediator.
Blood clotting cascade. The blood clotting cascade consists of the intrinsic and extrinsic pathway, both of which create thrombin, a protease involved in blood clotting. The intrinsic pathway requires kininogen, specifically high molecular weight kininogen, as a cofactor.