Send to

Choose Destination
Proc Natl Acad Sci U S A. 2013 Sep 24;110(39):15782-7. doi: 10.1073/pnas.1218880110. Epub 2013 Sep 3.

Blockade of the purinergic P2Y12 receptor greatly increases the platelet inhibitory actions of nitric oxide.

Author information

The William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London EC1M 6BQ, United Kingdom.


Circulating platelets are constantly exposed to nitric oxide (NO) released from the vascular endothelium. This NO acts to reduce platelet reactivity, and in so doing blunts platelet aggregation and thrombus formation. For successful hemostasis, platelet activation and aggregation must occur at sites of vascular injury despite the constant presence of NO. As platelets aggregate, they release secondary mediators that drive further aggregation. Particularly significant among these secondary mediators is ADP, which, acting through platelet P2Y12 receptors, strongly amplifies aggregation. Platelet P2Y12 receptors are the targets of very widely used antithrombotic drugs such as clopidogrel, prasugrel, and ticagrelor. Here we show that blockade of platelet P2Y12 receptors dramatically enhances the antiplatelet potency of NO, causing a 1,000- to 100,000-fold increase in inhibitory activity against platelet aggregation and release reactions in response to activation of receptors for either thrombin or collagen. This powerful synergism is explained by blockade of a P2Y12 receptor-dependent, NO/cGMP-insensitive phosphatidylinositol 3-kinase pathway of platelet activation. These studies demonstrate that activation of the platelet ADP receptor, P2Y12, severely blunts the inhibitory effects of NO. The powerful antithrombotic effects of P2Y12 receptor blockers may, in part, be mediated by profound potentiation of the effects of endogenous NO.


anti-platelet therapy; atherothrombosis; prostacyclin

[Indexed for MEDLINE]
Free PMC Article

Publication type, MeSH terms, Substances, Grant support

Publication type

MeSH terms


Grant support

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center