Procoagulation and anticoagulation Flashcards
Oxidized vitamin K is converted to reduced vitamin K (activated) by ____
Epoxide reductase
Which acts as a c0-factor: oxidized vitamin K or reduced vitamin?
Reduced vitamin K
Clotting factors that are vitamin K-dependent
II, VII, IX, X
Relationship of vitamin K and warfarin
It inhibits epoxide reductase, thereby inhibiting the activation of vitamin K
Vitamin K deficiency results in decreased synthesis of ____, ____, ____, ____, ____ and ____
Factors II, VII, IX, X, protein C, protein S
Role of vWF in procoagulation
vWF carries/protects VIII
- Memory aid:*
- volksWagen Factories make gr8 (great) cars
Action of protein C and protein S
For anticoagulation
- Memory aid:*
- C and S are _C_lot _S_toppers
Which molecule, found on the surface of vascular endothelial cells, is a cofactor in the activation of protein C, an anticoagulant?
Thrombomodulin, which is located on the surface of vascular endothelial cells
What does antithrombin inhibit? What are the pricipal targets?
- Activated forms of factors II, VII, IX, X, XI, XII
- Thrombin and factor Xa
Action of heparin
Heparin enhances the activity of antithrombin
Why do neonates receive an injection of vitamin K soon after birth?
Neonates lack enteric bacteria that produce vitamin K and can therefore be deficient in the vitamin K-dependent factors and suffer hemorrhagic disease
Name three endogenous factors that initiate anticoagulation
- Antithrombin III
- Protein C
- Plasminogen
What is the role of protein S in anticoagulation?
Protein S is a cofactor for protein C activation, which inactivates factors Va and VIIIa
How does plasminogen act as an anticoagulant?
Plasminogen is activated by tissue plasminogen activator to plasmin, which cleaves the fibrin clot
What is tissue plasminogen activator used for clinically?
As a thrombolytic in cases of acute stroke or myocardial infarction within hours of clot formation; tissue plasminogen activator activates plasminogen to plasmin
