Yan Antiplatelet and Fibrinolytic Session Quiz PDF

Aspirin: MOA (acetylation) Platelet Arachidonic acid Endothelium Arachidonic acid Low dose aspirin cyclooxygenase Cyclic endoperoxides TX synthetase TXA2 cAMP promotes Adhesion of platelets Higher dose aspirin Cyclic endoperoxides Prostacyclin synthetase Adenylate PGI2 cyclase cAMP inhibits A...

Aspirin: MOA (acetylation) Platelet Arachidonic acid Endothelium Arachidonic acid Low dose aspirin cyclooxygenase Cyclic endoperoxides TX synthetase TXA2 cAMP promotes Adhesion of platelets Higher dose aspirin Cyclic endoperoxides Prostacyclin synthetase Adenylate PGI2 cyclase cAMP inhibits Adhesion of platelets & Release of ADP and 5-HT Clopidogrel (ticlopidine, ticagrelor, prasugrel) ➢ ADP antagonist, irreversibly inhibits binding of ADP to its receptors Abciximab, Tirofiban and eptifibatide All prevent platelet aggregation by preventing fibrinogen crosslinking of platelets Abciximab irreversibly binds to GP IIa/IIIa receptors Unlike abciximab, tirofiban and eptifibatide are competitive reversible inhibitors of fibrinogen binding of GP IIb/IIIa receptors Fibrinolysis and sites of drug action Plasminogen Reteplase (rPA) Tenecteplase (TNK tPA) Anistreplase Urokinase Streptokinase Alteplase Fibrinogen Fibrin Plasmin Fibrin split products Degradation products Fibrinolytics All the drugs listed below can: ➢ Lyse the thrombi/clot to restore blood flow ➢ Activate the firbrinolytic system Streptokinase (not available in US) Alteplase (t-PA) Reteplase (r-PA) Tenecteplase (TNK-tPA) Urokinase Yan Antiplatelet and fibrinolytic session quiz 1. Aspirin can prevent platelet aggregation because it can inhibit the formation of: a. Arachidonic acid *b. Thromboxane A2 c. Plasmin d. Fibrin 2. Plasmin can be converted to plasminogen by a protease, thereby dissolving blood clot. a. True *b. False 3. Which of the following needs to be initially activated to achieve dissolution of blood clot? *a. Plasminogen b. Plasmin c. Fibrin d. Fibrinogen 4. Which of the following is an irreversible inhibitor of platelet ADP receptor? a. Aspirin b. Epifibatide *c. Prasugrel d. Dipyridamole 5. Aspirin acetylates which of the following? a. Adenylate cyclase b. Prostcyclin synthase c. Plasminogen *d. Cyclooxygenase e. cAMP 6. The following drug shown in the image: A. Is derived from uric acid. B. Can modify COX 1 and activates it. *C. Can decrease the production of thromboxane A2 in cells. D. Suppresses primarily the secondary hemostasis process. 7. Look at the image below, where is the pharmacophore of eptifibatide for its antiplatelet activity? *A. a B. b C. c 8. Which of the following statements about the four metabolites of ticlopidine shown in the image below is correct? A. Metabolite 1 is a toxic metabolite. *B. Metabolite 2 is an active metabolite that inactivates P2Y12 purinergic receptor. C. Metabolites 3 and 4 have potent antiplatelet activity. D. The production of these four metabolites doesn’t require cytochrome P450 (e.g., CYP3A4). 9. Which of the following statement about tirofiban is INCORRECT? A. Tirofiban mimics the structure of Lys-Gly-Asp sequence found in eptifibatide. B. Tirofiban targets glycoprotein llb/llla receptor. *C. Tirofiban is a peptide drug. D. Tirofiban prevents platelet from aggregation. 10. Which of the following statements about thrombolytic agents is correct? A. Urokinase is an enzyme that phosphorylates fibrin B. Alteplase is smaller than reteplase by 172 amino acids *C. Alteplase, reteplase and tenecteplase are serine proteases D. Streptokinase has high selectivity to only digest plasminogen bound to fibrin