Block 2 - Antiplatelets Med Chem Flashcards
What are the anti platelet drugs?
- Aspirin
- Glycoprotein IIb/IIIa inhibitors
- ADP inhibitors (clopidogrel)
- PDE/adenosine uptake inhibitors
Describe how platelet aggregation occurs?
Understand platelet aggregation cascade Slides 5-8
What is the MOA of COX1 inhibitors?
Block the synthesis of thromboxane A2
What is thromboxane A2?
key inducer of platelet aggregation → a potent vasoconstrictors at high concentration
Describe the effects of acetylsalicylic acid?
Aspirin is an Irreversible inhibitor of COX-1
What gives aspirin is lasting aggregation effect?
Lifetime of the platelet and platelets can replicate
What are PDE inhibitors do?
Leads to increased cAMP leads to negative effect on intracellular calcium levels → drug inhibits → Low intracellular calcium levels inhibit aggregation
Promotes the conversion of cAMP → AMP
What are the PDE3 inhibitors for platelet aggregation?
- Dipyridamole
- Cilostazol (more selective)
What do PDE3 inhibitors need to mimic?
cAMP
What is the MOA of P2Y purinergic receptor?
Targets P2Y12 that promotes ADP binding → intracellular Ca2+
Antagonists → slow activation GP IIb/IIIa receptors → prevents aggregation
What is the SAR of P2Y antagonists?
ADP mimicry
What are the ADP binding sites on platelets? Function?
Px1, P2Y1, P2Y12
Increases intracellular Ca2+
What are P2Y antagonists? Which are prodrugs?
- Ticlopidine
- Clopidogrel
- Prasugrel
- Ticagrelor (Not prodrug)
What P2Y antagonists are metabolized by CYP?
- Clopidogrel
- Ticagrelor
- Ticlopidine
CYP2C19
Brand name Ticagrelor
Brilinta
What are the newest anti platelet aggregators?
Glycoprotein IIb/IIIa Receptor Antagonists
MOA of Glycoprotein IIb/IIIa Receptor Antagonists?