Blood clotting Flashcards
Factor I
fibrinogen (fibrin)
common pathway
Factor II
prothrombin (thrombin)
serine protease
contains Gla
all pathways
Gla
gamma-carboxylate, calcium chelator
Factor III
tissue factor (TF)/thromboplastin
accessory protein
extrinsic pathway
Factor IV
calcium
all pathways
Factor V
proaccelerin
accessory protein
common pathway
Factor VII
proconvertin
serine protease
contains Gla
extrinsic pathway
Factor VIII
antihemophilic factor
accessory protein
intrinsic pathway
Factor IX
Christmas factor
serine protease
contains Gla
intrinsic pathway
Factor X
Stuart factor
serine protease
contains Gla
all pathways, initiates common pathway
Factor XI
plasma thromboplastin antecedent
serine protease
intrinsic pathway
Factor XII
Hageman Factor
serine protease
intrinsic pathway
Factor XIII
fibrin stabilizing factor
converts clots from soft to hard
create fibrin cross-links between Lys and Gln residues
serine protease factors
II, VII, IX, X, XI, XII
Gla-containing factors
II, VII, IX, X
accessory protein factors
III, V, VIII
factors activated by thrombin (IIa)
I, V, VII, VIII, XI, XIII
plasmin
serine protease
generated from plasminogen
incorporated into clots along with fibrin and TPA
protected from inhibitors along with TPA until clot dissolves
antithrombin (ATIII)
serpin (serine protease inhibitor)
inactivates thrombin
affinity for thrombin enhanced when bound to the anticoagulant heparin
protein C-protein S complex
protein C binds to thrombin, decreases thrombin affinity for fibrinogen
thrombomodulin upregulates thrombin affinity for protein C, making thrombin a protein of anticoagulation
protein C+protein S=APC
APC cleaves factors V and VIII
von Willebrand factor (VWF)
mediates platelet-collagen binding
binds to and stabilizes factor VIII in blood
allows for platelet adhesion
deficiency of factor XII
no bleeding disorder!
Hemophilia A
classic hemophilia
deficiency in factor VIII
Hemophilia B
Christmas disease
deficiency in factor IX
Hemophilia C
deficiency in factor XI
von Willebrand disease
most common coagulopathy
deficiency in VWF
heavier and prolonged bleeding, mild to severe
(inability to bind to factor VIII)
