Which receptor on platelets corresponds to binding collagen?

Which receptor on platelets corresponds to binding collagen?

• A. Receptor for fibrinogen
• B. Receptor for von Willebrand factor
• C. Receptor for collagen
• D. Receptor for platelet adhesion to endothelium

Answer: (C)

When a vessel is injured, collagen is exposed and platelets must attach directly to it. Platelets have specialized receptors to recognize collagen, with the primary signaling receptor being GPVI. Binding collagen via GPVI activates the platelet, initiating the release of granule contents and recruitment of more platelets, which leads to aggregation through another receptor (GPIIb/IIIa) binding fibrinogen. A secondary collagen-adherence receptor, integrin α2β1, helps strengthen the attachment to collagen. The other receptors mentioned are involved in different steps: the fibrinogen receptor binds circulating fibrinogen to cross-link platelets after activation, and the von Willebrand factor receptor mediates initial tethering to sites where von Willebrand factor is present. Therefore, the receptor that corresponds to binding collagen is the collagen receptor on platelets (GPVI, with α2β1 also contributing).

When a vessel is injured, collagen is exposed and platelets must attach directly to it. Platelets have specialized receptors to recognize collagen, with the primary signaling receptor being GPVI. Binding collagen via GPVI activates the platelet, initiating the release of granule contents and recruitment of more platelets, which leads to aggregation through another receptor (GPIIb/IIIa) binding fibrinogen. A secondary collagen-adherence receptor, integrin α2β1, helps strengthen the attachment to collagen. The other receptors mentioned are involved in different steps: the fibrinogen receptor binds circulating fibrinogen to cross-link platelets after activation, and the von Willebrand factor receptor mediates initial tethering to sites where von Willebrand factor is present. Therefore, the receptor that corresponds to binding collagen is the collagen receptor on platelets (GPVI, with α2β1 also contributing).