Coagulation and Clotting Flashcards
GPIa - GPIIa
Receptor for collagen
GPIb
Receptor for Von willebrand factor
Platelet alpha granules
Fibrinogen, platelet derived growth factor, vWF, P-selectin, platelet factor 4 (PF4)
Platelet dense granules
ADP, ATP, serotonin (5-HT), calcium
Thrombin promotes these in coagulation pathway
Fibrinogen to fibrin V to Va XIII to XIIIa VIII to VIIIa XII to XIIa
Factors in extrinsic pathway
VII
Factors in intrinsic pathway
XII,XI,IX,VIII,prekallikrein, high molecular weight kininogen (HMWK)
Factors in common pathway
X,II (thrombin), I (fibrinogen)
Tenase complex
Forms on surface of platelets.
IXa,VIIIa, calcium
Activates X to Xa
Intrinsic pathway
Anchors the Tenase and prothrombinase complexes to platelet
Phophatidleinositol and phophatidlyserine
Prothrombinase complex
Va and Xa
Antithrombin
Inactivates thrombin, IXa,Xa,XIa,XIIa
Stimulated by heparin
Activated protein c (APC)
Inactivates Va and VIIIa with protein S as cofactor
tPA
Tissue plasminogen activator. Coverts plasminogen to plasmin. Released from vasculature endothelial cells with injury.
Bleeding time
Elevated in Von Willebrand disease, other inherited platelet disorders, uremia, aspirin use, low platelet count