Final answer:
Abciximab is the antithrombotic agent that resembles RGD and specifically binds to platelet integrin to prevent platelet aggregation. Aspirin, Warfarin, and Heparin are anticoagulants that work through different mechanisms.
Step-by-step explanation:
The antithrombotic agent that resembles RGD and binds only to the platelet integrin is d) Abciximab. Abciximab is an inhibitor of the platelet glycoprotein IIb/IIIa receptor, which is a platelet integrin. As an antagonist of this receptor, abciximab prevents platelet aggregation by mimicking the natural ligands, like RGD (arginine-glycine-aspartate), that would normally bind to the receptor and cause platelet clumping. This selective inhibition makes it effective in reducing the risk of thrombosis in certain clinical settings.
On the other hand, Aspirin acts as an anticoagulant by inhibiting cyclooxygenase, thus preventing the formation of thromboxane A2, a molecule that promotes platelet aggregation. While Warfarin and Heparin are also anticoagulants, they work through different mechanisms unrelated to platelet integrin binding. Warfarin inhibits vitamin K epoxide reductase, affecting the synthesis of certain clotting factors. Heparin enhances the activity of antithrombin III, thereby inhibiting thrombin and factor Xa, which are crucial in the clotting cascade.