Antiplatelet & Fibrinolytic drugs

Question 1

Venous thrombosis vs arterial thrombosis?

Answer 1

Venous = high red blood cell and fibrin content, low platelet
Arterial = Lower fibrin content and higher platelet content

Question 2

How does prostacyclin inhibit platelet aggregation?

Answer 2

it binds to platelet receptors increasing cAMP in platelets, decreasing calcium and preventing aggregation. Also stabilises GP2b/3a receptors

Question 3

Name 2 types of platelet granules?

Answer 3

ADP and thromboxane

Question 4

What do platelet granules do?

Answer 4

Initiate activation and aggregation ultimately through GP2b/3a receptors and fibrinogen

Question 5

How do Cyclo-oxygenase inhibitors work?

Answer 5

Inhibit COX-1 mediated production of Thromboxane A2 and reduces platelet aggregation irreversibly

Question 6

Aspirin s used for secondary prevention of what?

Answer 6

Stroke, TIA and ACS

Question 7

What is the loading dose of aspirin for ACS?

Answer 7

300mg (chewable is best)

Question 8

How do ADP receptor antagonists work?

Answer 8

inhibit binding of ADP to P2Y12 receptor, inhibiting activation of GP2b/3a receptors

Question 9

How do glycoprotein 2b/3a inhibitors work?

Answer 9

Blocks binding of fibrinogen and von willebrand factor

Question 10

How do phosphodiesterase inhibitors work?

Answer 10

inhibits cellular reuptake of adenosine, increased plasma adenosine and inhibits aggregation of platelets via A2 receptors

Question 11

How do fibrinolytics work?

Answer 11

Dissolve the fibrin meshwork of thrombus