Mechanisms of Clotting Flashcards
What can happen if you get clotting at the wrong place at the wrong time?
Might develop a thrombus
What can a thrombus lead to?
It might break off and deposit someone else.
Can lead to issues like myocardial infarction, stroke or pulmonary embolism.
What are the two mechanisms required for blood clotting?
Formation of a platelet plug
Formation of a fibrin clot
What lines blood vessels?
Endothelium
The basement membrane in which endotherlium sits on is mostly composed of what?
Collagen
What happens if blood vessels are damaged?
Platelets are exposed to collagen.
Platelets become activated and stick to the collagen.
Platelet plug forms
Is a platelet plug strong or weak?
Weak
After the formation of a platelet plug, what happens?
A fibrin clot forms
Describe fibrin.
Large, insoluble protein
How is fibrin formed?
Formed from fibrinogen by the enzyme thrombin.
Describe how the endothelium prevents platelets coming into contact with collagen.
Forms a physical barrier, inhibiting platelet aggravation.
What does the endothelium secrete to prevent the platelet aggravation.
Prostacyclin and nitric oxide
What can the endothelium produce to prevent thrombin production?
Tissue factor pathway inhibitor (TFPI)
What can bind to thrombin and inactivate it?
Thrombomodulin
If there is a blood clot formed, what can the endothelium secrete to combat this?
Tissue plasminogen activator (t-PA
