Coagulation Flashcards
Match each mediator with its primary function in the blood:
Protein C, Plasminogen activation inhibitor, Von Willebrand factor, tPA
Procoagulant, anticoagulant, antifibrinolytic fibrinolytic
Von Willebrand factor- procoagulant
Protein C- anticoagulant
tPA- fibrinolytic
plasminogen activation inhibitor- antifibrinolytic
When there’s a vascular injury, the body attempts to prevent
hemorrhage
What steps does the body take to prevent hemorrhage?
vascular spasm
formation of platelet plug (primary hemostasis)
coagulation and fibrin formation (secondary hemostasis)
fibrinolysis when the clot is no longer needed
When there is no injury, blood remains
as a liquid
How does blood maintain as a liquid?
coagulation proteins circulate in inactive form
the endothelium is smooth & the glycocalyx repels clotting factors
undamaged endothelium does not express tissue factor or collagen
There’s a delicate balance between factors that
create clots & those that prevent clots; A disruption can lead to pathology
Both arteries and venous are made of
3 layers
The three layers of arteries and veins include
tunica externa (connective tissue)
tunica media (smooth muscle layer & elastic tissue)
tunica intima (endothelium)
The three layers of arteries and veins include
tunica externa (connective tissue)
tunica media (smooth muscle layer & elastic tissue)
tunica intima (endothelium)
If procoagulants predominate, then the blood tends to
clot
Procoagulants and antifibrinolytics favor
clot formation
If anticoagulants predominate, then the blood has a tendency
not to clot
Anticoagulants and fibrinolytics favor
clot destruction
Coagulation factors, collagen, wVF, fibronectin, and thrombomodulin are all
procoagulants
Protein C, protein S, antithrombin, tissue pathway factor inhibitor are all
anticoagulants
Plasminogen, tPA, urokinase are all
fibronlytics
Alpha-antiplasmin and plasminogen activator inhibitor are
antifbrinolytics
Vasoactive mediators that cause vasoconstriction include
thromboxane A2, ADP, serotonin
Vasoactive mediators that cause vasodilation include
nitric oxide
prostacyclin
__________– breaks down plasmin
plasminogen
________ & _____________ activates plasmin
Urokinase and tPA
What is a cofactor for protein C?
Protein S
Protein C is responsible for
degrading factor 5a & 8a
Antithrombin inactivates
2a (thrombin)
factors 9a, 10a, 11a, & 12a
Tissue pathway factor inhibitor is responsible for
inhibiting tissue factor
Coagulation factors promote
coagulation
Collagen provides
tensile strength
Von Willebrand factor provides
platelet adhesion
Fibronectin is responsible for
cell adhesion
____________- regulates naturally occurring anticoagulants
Thrombomodulin
Alpha antiplasmin
inactivates tPA, urokinase
Plasminogen activator inhibitor
inhibits plasmin
Platelets contain the following components EXCEPT:
a. actin
b. deoxyribonucleic acid
c. adenosine diphosphate
d. calcium
b. deoxyribonucleic acid
Normal value of platelets is
150,000-300,000/mm3
The lifespan of platelets is
8-12 days (1-2 weeks)
The spleen can sequester up to
1/3rd of all circulating platelets for later use
Platelets are a
structural component of the clot
Platelets are essential delivery vehicles that provide
many substrates required for clot formation
Megakaryocytes produce platelets in
the bone marrow
Components of the platelet on the external membrane include
glycoproteins
phospholipids
Components of the inside of the platelet include
actin & myosin
thrombosthenin
ADP
calcium
fibrin-stabilizing factor
serotonin
growth factor
In the absence of vascular injury, the endothelium inhibits platelet function by secreting:
nitric oxide- inhibits TxA2 receptor
prostaglandin 12- inhibits vWF adherence, TxA2 activation, and release of storage granules
Platelet receptors that exist on the platelet include
ADP
GPIb
TxA2
Thrombin
GPIIb-IIa
Platelets are cleared by
macrophages in the reticuloendothelial system and the spleen
