DueThurday, Noveber 9 at 240 PM The formation of a blood clot involves two different processes that occur at the site of injury to coagulation cascade that the blood vessel: the activation and aggregation of platelets; and the blood culminates in the creation of a net-like structure of cross-linked fibrin proteins. that describes drugs that inhibit platelet activation and/or aggregation. Four are aspirin, dipyridamole, clopidogrel, and abciximab. The directed to a different target molecule in the platelet activation process. The mol for these “Antiplatelets” is a term antiplatelet drugs mechanism of action of each drug is ecular target molecules are, in no particular order, active P2Y receptors, von Willebrand Factor (WF), cyclie- AMP (CAMP), and thromboxane The principal role that each target molecule plays in the platelet activation/aggregation process, in no particular order, is as follows: inhi biting adenylate cyclase, which lowers the cellular concentration of cAMP to intercellular GPllb/11la receptors and thereby cross-linking adjacent activated platelets; inhibiting platelet activation; and increasing the density of GPIbIla receptors on the surfaces of platelets, which in turn promotes the cross-linking and aggregation of the activated platelets. principal mechanism of action of each drug in inhibiting the platelet activation/aggregation process, in no particular order, is as follows irreversibly inactivating P2Y receptors; inhibiting the binding of vWF to GPllb/Illa receptors; inhibiting thromboxane biosynthesis; and increasing the concentration of cAMP Use the following clues to match the antiplatelet drug with its corresponding target molecule and mechanism. Then answer the the effect that the drug exerts on the platelet activation/aggregation questions on Blackboard for On-Line Quiz #19. ue #1 Dipyridamole, which does not interact with P2Y receptors, increases the concentration Clue #2 Aspirin increases the density of GPnblla receptors on the surfaces of platelets, but it Clue #3-Clopidogrel does not inhibit the binding of vwF to GPilla receptors, nor does it Clue #4-The drug that inhibits the binding of vWF to Gribilla receptors prevents vWF from Cl of cAMP by inhibiting its hydrolysis. doesn’t inhibit the binding of vWF to existing GPIIbIIla receptors. inhibit the biosynthesis of thromboxane. cross-linking adjacent activated platelets. Clue #5 The drug that irreversibly inactivates P2Y receptors prevents the inhibition of adenylate cyclase, causing the cellular concentration of cAMP to be lowered Clue #6-Thromboxane does not inhibit platelet activation.