Hemostasis Flashcards
Where is thrombopoietin produced?
It is produced by the liver and to a lesser extent, the kidney.
What all is contained in the vesicles of a platelet?
ADP
Thromboxane A2
Fibrin stabilizing factor
Platelet derived growth factor
What is the function of cyclooxygenase 1?
Conversion of arachidonic acid into prostaglandins (like thromboxane A2)
What are the four steps of hemostasis?
Vascular spasm
Platelet plug
Blood clot
Repair
What three chemicals act as short term vasoconstrictors to assist with the vascular spasm phase of hemostasis?
Thromboxane A2
Platelet factor
Serotonin
What are the two steps for the formation of a platelet plug?
- Collagen is exposed -
Step 1: Von Willebrand factor binds
Step 2: Platelet’s collagin receptor binds and is activated
What does thrombin do to help form a clot?
What does it do to get rid of a clot?
To form the clot: fibrinogen → fibrin
To get rid of the clot,
Protein C → Activated protein C
What is the function of protein C in clot removal?
It inactivates the tPA inhibitor
This allows tissue plasminogen activator (tPA) to activate plasminogen into plasmin.