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Question 2

Function of hemostasis

Answer 2

Limit blood loss

Question 3

Define thrombosis

Answer 3

Formation of blood clot inside the vessel

Question 4

Endothelium has a non-thrombogenic surface

Answer 4

If this is intact, it generates prostaglandin and nitric oxide which inhibits platelet aggregation

Question 5

When endothelium is damaged, sub-endothelial collagen is exposed and platelets will adhere to this - this will activate the platelets

Answer 5

The platelets will begin to Aggregate

Question 6

Platelets release agents which promote vasoconstriction and platelet aggergation

Answer 6

Then fibrin will form through enzymatic reaction, these get meshed within the platelet plug, which stops the flow

Question 7

Haemostatic plug is dissolved by fibrinolytic system

Answer 7

.

Question 8

“Blood clot” slide

Answer 8

Shows EMG of RBC in fibrin mesh

Question 9

Calcium is required for clotting

Answer 9

Calcium chelators can be used to prevent clotting

Question 10

Thrombin acts on

Answer 10

Fibrinogen to form fibrin

Question 11

Extrinsic factor = the Easy pathway

Answer 11

.

Question 12

Blood clotting disorders

Answer 12

Learn

Question 13

Fibrinolytic system stops the clotting cascade overrunning

Answer 13

Plans in breaks down fibrin polymers

Question 14

Venous thrombosis vs arterial thrombosis

Answer 14

Problem with venous thrombosis - can break off and enter pulmonary circulation

Question 15

Anticoagulants are involved in vitro storage of blood, as well as in vivo

Answer 15

Heparin - is polyanionic (has lots of negative charges)

Question 16

Calcium chelators and heparin are main anticoagulants in vitro

Answer 16

EDTA is a chelator

Question 17

In vivo use of anticoagulants

Answer 17

Heparin - given intravenously Warfarin - given orally

Question 18

Heparin binds to antithrombin 3

Answer 18

Heparin antithrombin 3 complex binds to various clotting factors, inhibiting clotting cascade

Question 19

Low MW heparin works differently from heparin

Answer 19

Binds factor 10a

Question 20

LMWH does not inactive thrombin, but Unfractionated heparin does

Answer 20

,

Question 21

Side effects of heparin

Answer 21

Allergic reactions Haemorrhage Heparin induced thrombocytopenia (reduced platelet level, therefore platelet plug less likely to form)

Question 22

Main oral anticoagulant is Warfarin - a structural analogue of vitamin K

Answer 22

Blocks synthesis of coagulation factors in the liver

Question 23

Vitamin K required for caboxylation of certain clotting factors

Answer 23

.

Question 24

S warfarin and R warfarin

Answer 24

.

Question 25

Warfarin ends up bound to plasma albumin, other drugs can displace warfarin from binding sites on albumin

Answer 25

Example is aspirin

Question 26

NSAIDs and warfarin don’t mix

Answer 26

.

Question 27

New oral anticoagulants

Answer 27

5

Question 28

Aspirin irreversibly inhibits COX enzymes

Answer 28

Acetylation

Question 29

Clopidogrel

Answer 29

Blocks platelet ADP receptors

Question 30

Abciximab - MAB

Answer 30

Only used once??