Coagulation Cascade Flashcards
What are the antithrombotic properties of the intact endothelial vessel wall?
- Negativity charged heparin like glucosamino glycans.
*Neutral phospholipids - Platelet and coagulation factor inhibitors
- Fibrinolysis activators
What are the Thrombogenic factors of subendothelium ?
*Subendothelial collagen
*VWF
* Laminin, thrombospondin, and vitronectin ( involved in platelet adhesion)
What is the acute effect of vascular insult?
Acute vascular insult causes neurogenic reflex vasospasms and local release of endothelin and platelet derived Thromboxane A2.
What are the circulating Thrombogenic factors?
Platelets
Platelet activating factors
Clotting factors
Prothrombin
Fibrinogen
vWF
What are the circulating antithrombigenic factors?
TPA
Antithrombin
Protein C and S
Plasminogen
What are the contents of alpha granules of platelet?
- P-selectin
*Fibrinogen and fibronectin
*Factor V and VIII - Platelet factor IV
- Platelet derived growth factor
- TGF-Alpha
What are the contents of delta or dense granules of platelets?
- ATP, ADP, calcium
- Serotonin
- Histamine
- Epinephrine
What are the steps of primary hemostasis ?
- Platelet adhesion
- Platelet secretion/ degranulation
- Platelet aggregation
What happen during platelet adhesion ?
The vWF acts as a bride between endothelial collagen and platelet surface receptor GP1b promotes platelet adhesion.
What happen during platelet degranulation?
It is marked by degranulation of alpha and dense granules by secreting calcium and other substances. Calcium binds to the circulating phospholipids ( secondary to platelet activation) and provide binding sites for coagulation factors.
What happen during platelet aggregation?
Thromboxane A2 and ADP promotes platelet aggregation by crosslinking platelets via GP2b3a.
What is the mechanism of localized primary plug formation?
The fine balance between the Thrombogenic factor Thromboxane A2 and antithrombigenic factor Prostacycline prevents the extension of the clot.
Deficiency of Glycoprotein IIb/IIIa cause?
Glanzmann thrombathenia
Deficiency of Glycoprotein Ib cause?
Bernard Soulier syndrome
