P2Y12 is an adenosine diphosphate (ADP) receptor located on platelet cell membranes. Clopidogrel functions by inhibiting this receptor. A P2Y12 assay measures the inhibition of platelet function due to clopidogrel ingestion.
The VerifyNow™ P2Y12 assay (Accumetrics) is another automated platelet aggregation test. It measures the level of platelet P2Y12 receptor inhibition. The testing system employs single-use cartridges so that the test can be performed at the point-of-care as well as in the laboratory. Like the company's aspirin response test, it measures platelet-induced aggregation as an increase in light transmittance. The required specimen is citrated whole blood. ADP is used as the agonist in this test. The results are reported in P2Y12 Reaction Units (PRU).