Activation of which receptor leads to sustained platelet aggregation?

The activation of the P2Y12 receptor plays a crucial role in the process of sustained platelet aggregation. This receptor is a type of purinergic receptor that is sensitive to adenosine diphosphate (ADP), a key signaling molecule released by activated platelets. When ADP binds to P2Y12, it causes a conformational change in the platelets, leading to enhanced integrin αIIbβ3 activation on their surface. This integrin is essential for the final step of platelet aggregation, facilitating the binding of fibrinogen and linking platelets together, thereby forming a stable platelet plug.

The P2Y12 receptor is also significant in the context of antiplatelet therapy. Medications that specifically target this receptor, such as clopidogrel and ticagrelor, are used to prevent unwanted platelet aggregation, particularly in patients with cardiovascular disease. Inhibition of this receptor reduces the platelet response to ADP, thereby minimizing the risk of thrombus formation.

While the other receptors mentioned may contribute to different aspects of platelet activation or aggregation, the P2Y12 receptor is specifically responsible for sustaining the aggregation process once initiated, making it the critical target for ensuring effective platelet response during hemostasis or in