Hemostasis

Question 1

Factor I

Answer 1

Fibrinogen

Question 2

Factor II

Answer 2

Prothrombin

Question 3

Factor III

Answer 3

Thromboplastin

Question 4

Factor IV

Answer 4

Calcium

Question 5

Factor V

Answer 5

Proccelerin

Question 6

Factor VII

Answer 6

Proconvertin

Question 7

Factor VIII

Answer 7

Antihemophilic factor

Question 8

Factor IX

Answer 8

Christmas factor

Question 9

Factor X

Answer 9

Stuart-Prower factor

Question 10

Factor XI

Answer 10

Plasma thromboplastic antecedent (PTA)

Question 11

Factor XII

Answer 11

Hageman factor

Question 12

Factor XIII

Answer 12

Fibrin stabilizing factor

Question 13

Fibrinolysis Fragments

Answer 13

D fragements double bond with each other, E single bonds
DD/E
DxD/DD
DY/YD

Question 14

Primary Hemostasis

Answer 14

Involves the function of blood vessels and platelets in blood clot formation

Question 15

Platelets

Answer 15

80% are in circulation, 20% are in the spleen
4-5 days to mature, 9-12 days in circulation
Activated by thrombin, PTA, lysophosphatidic acid, thromboxane A2, ADP, and serotonin

Question 16

Peripheral Zone

Answer 16

Membrane: negatively charged phospholipids, GPIb bind vWF, GPIIIb/IIIa bind fibrinogen
Glycocalyx: gives a negative charge to platelets, provides a thick layer of glycoproteins/glycolipids/mucopolysaccharides where coagulation factors can bind (I, II, VII, vWF, IX, X)

Question 17

Structural Zone

Answer 17

Microfilaments

Microtubules (actin and myosin)

Question 18

Membrane Zone

Answer 18

Open canalicular system: channels leading from plt surface to interior, release granule content
Dense tubular system: smooth ER from megakaryocyte, acts as store of Ca2+

Question 19

Organelle Zone

Answer 19

Mitochondria: 50% of ATP from respiration, glycolysis
Glycogen
Storage granules

Question 20

Dense Granules

Answer 20

ADP, ATP, Ca2+, Serotonin

Question 21

Alpha Granules

Answer 21

Hemostatic proteins (I, V, XI, XIII, vWF, plasminogen)

Question 22

Protease Inhibitors

Answer 22

AAT, alpha 2macroglobulin, C1 esterase inhibitor, alpha2 antiplamin

Question 23

Platelet Specific Proteins

Answer 23

PF4, B thromboglobulin, PDGF, thrombospondin

Question 24

Platelet Adhesion vs Aggregation

Answer 24

Adhesion: plts adhere to exposed collagen/vWF through GPIb receptor, causes shape change, Ca2+ released from DTS
Aggregation: attachment of plts to each other, ATP dependent process, fibrinogen binds to the GPIIb/IIIa receptor

Question 25

Granules Release

Answer 25

1st group: dense granules | 2nd group: 1 release (alpha), 2 release (dense and lysosomes)

Question 26

Secondary Hemostasis

Answer 26

Involves the coagulation cascade which forms a fibrin mesh around the platelet plug

Question 27

Extrinsic Pathway

Answer 27

Activated by tissue damage/factor and trauma Shorter pathway Measured by PT Vessel injury - TF and VII - TF and Ca++ and VIIa (Xase complex)

Question 28

Intrinsic Pathway

Answer 28

Activated by negatively charged surface Measures by PTT Roles in fibrinolysis, inflammation, and complement activation Contact - XII and XIIa - XI and XIa - Ca++ - IX - IXa and VIIIa and PL and Ca++ (Xase)

Question 29

Factor VIII and vWF

Answer 29

Factor VIII: produced by liver, circulated bound to vWF to prevent degrading, activated by thrombin which releases it from vWF, binds to platelet phospholipid surface vWF: made by endothelial cells, large glycoprotein cut by ADAMTS13, links platelets to collagen via the GPIb receptor

Question 30

Xase

Answer 30

Extrinsic: TF, VIIa, X, IX (intrinsic IX to IXa, prothrombinase X to Xa) Intrinsic: VIIIaH, VIIIaL, X, IXa (prothrombinase X to Xa) Prothrombinase: VaH, VaL, II, Xa (protein case II to IIa) Protein case: Tm, IIa, PC (PC to APC)

Question 31

Common Pathway

Answer 31

``` Converts fibrinogen (factor I) into fibrin Also converts prothrombin (factor II) into thrombin X - Xa - Xa and Va and PL and Ca++ - Prothrombin to thrombin - XIII to XIIIa - Fibrin to cross-linked fibrin ```

Question 32

Fibrinolysis

Answer 32

Degrades fibrin to keep vessels clear to carry blood Inhibitors: a2-antiplasmin, TAFI, PAI1, PAI2, a2-macroglobulin Plasminogen activators: tPA, urokinase, streptokinase, XII/HMWK/PK Plasminogen is a zymogen and acute phase reactant protein Called plasmin when it activates and degrades fibrin polymers

Question 33

Intrinsic, Extrinsic, and Exogenous Pathway

Answer 33

Intrinsic: XII (contact HMWK) XIIA -- Prekallikrain to Kallikrein Extrinsic: tPA and urokinase Exogenous: Plasminogen (streptokinase) plasmin -- Fibrin to fibrin degradation products

Question 34

Fibrin Digestion by Plasmin

Answer 34

X fragment: DED Y fragment: DE Plasmin can't break crosslinked Ds (how we test for clots) All act as competitive inhibitors of plasmin

Question 35

Physiological Inhibition of Coagulation

Answer 35

Protein C system, TF pathway inhibitor, antithrombin

Question 36

Protein C System

Answer 36

Protein C and S are vitamin K dependent Protein C is activated by thrombin-thrombomodulin complex Protein C-S complex degrades factors Va and VIIIa

Question 37

Tissue Factor Pathway Inhibitor

Answer 37

Function enhanced by Protein S | Only inhibits extrinsic pathway after factor Xa has been made

Question 38

Antithrombin

Answer 38

Can inhibit thrombin and any other serine proteases | IXa, Xa, XIa, XIIa, kallikrein, and plasmin