title: Effect of genetic variation in P2Y12 on TRAP-stimulated platelet response in healthy subjects.
abstract: In platelets, thrombin receptor signaling depends upon the release of adenosine diphosphate and subsequent activation at purinergic subtype Y (P2Y) receptors. The purpose of this study is to evaluate the influence of specific P2Y12 polymorphisms on platelet reactivity in healthy subjects mediated by thrombin receptor activating peptide (TRAP). We recruited a total of 29 healthy volunteers who had been previously genotyped for two polymorphisms of the P2Y12 receptor: the H2 haplotype (rs2046934) and 34C>T (rs6785930). Flow cytometry and the VerifyNow assay were used to assess platelet activation and aggregation stimulated by TRAP in the presence and absence of specific receptor antagonists for the P2Y1, P2Y12, and thromboxane A2 receptors. We identified a significant recessive effect of the P2Y12-receptor H2 haplotype on TRAP-induced flow cytometry. Specifically, H2/H2 carriers (n = 5) demonstrated a significant reduction in both glycoprotein IIb/IIIa receptor activation (p < 0.001) and CD62P expression (p = 0.035). While the VerifyNow assay did not reveal any effect of haplotype on TRAP-mediated platelet aggregation (p = 0.72), the H2/H2 subjects demonstrated greater platelet inhibition in the presence of cangrelor, a specific receptor antagonist for the P2Y12 receptor (p = 0.023). No consistent effects of the separate 34C>T genotype (rs6785930) were demonstrated under the conditions evaluated. The findings of this study suggest a potential association between P2Y12-receptor H2/H2 carriers and reduced platelet function mediated by TRAP in healthy volunteers.
authors: Department of Pharmacy Practice, College of Pharmacy, University of Nebraska Medical Center, Omaha, NE, 68198-6045, USA, joestreich@unmc.edu.
authors: Julie H
authors: JH
authors: Oestreich
authors: Steven R
authors: SR
authors: Steinhubl
authors: Suellen P
authors: SP
authors: Ferraris
authors: Charles D
authors: CD
authors: Loftin
authors: Wendell S
authors: WS
authors: Akers
mesh_terms: D000249:Adenosine Monophosphate / Q000031:analogs & derivatives / Q000494:pharmacology; D000328:Adult; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects / Q000235:genetics; D006239:Haplotypes; D006801:Humans; D008297:Male; D019007:P-Selectin / Q000096:biosynthesis; D010446:Peptide Fragments / Q000494:pharmacology*; D010974:Platelet Aggregation / Q000187:drug effects / Q000235:genetics; D011110:Polymorphism, Genetic; D058921:Purinergic P2Y Receptor Antagonists / Q000494:pharmacology; D058925:Receptors, Purinergic P2Y12 / Q000235:genetics / Q000378:metabolism
chemical_list: D019007:P-Selectin; C548576:P2RY12 protein, human; D010446:Peptide Fragments; D058921:Purinergic P2Y Receptor Antagonists; D058925:Receptors, Purinergic P2Y12; C546937:SELP protein, human; C086309:thrombin receptor peptide SFLLRNP; D000249:Adenosine Monophosphate; C117446:cangrelor