Mechanism of action of homocysteine and its thiolactone in hemostasis system.

In the article, the actions of homocysteine (Hcys) and its metabolite - cyclic thioester - homocysteine thiolactone (HTL) on complex process of hemostasis, which regulates the flowing properties of blood, are described. Possible interaction of Hcys and HTL with endothelial cells, blood platelets, plasmatic fibrinogen and plasminogen, as the important major components of hemostasis are also discussed. The modification of hemostatic proteins (N-homocysteinylated or S-homocysteinylated proteins) induced by Hcys or its thiolactone, and links of homocysteine or homocysteine thiolactone to "NO metabolism seem to be the main reason of biotoxicty of homocysteine in cardiovascular diseases.