Protein Z and Ischemic Stroke

protein Z (PZ) is a vitamin K-dependent plasma glycoprotein synthesized by the liver. Its structure is similar to other vitamin K-dependent coagulation factors. PZ plays an important role in mediating thrombosis and may be an independent risk factor for ischemic strokes. PZ mainly promotes the assembly of thrombus with phospholipids surfaces in a Ca2+-dependent fashion, thus enhancing coagulation. On the other hand, PZ binds with a specific PZ-dependent protease inhibitor (ZPI) to factor Xa and therefore indirectly acts as a natural anticoagulant. Therefore, PZ plays two paradoxical roles in vivo. It is connected with coagulation and anticoagulation and ischemic stroke. More research is needed to improve our understanding of PZ's role in preventing and treating thrombosis.