title: Inhibition of ADP-induced platelet aggregation by clopidogrel is related to CYP2C19 genetic polymorphisms.
abstract: 1. Clopidogrel is one of the most important antithrombotic drugs but has different efficacies in different populations. The aim of the present study was to evaluate the contribution of CYP2C19 genetic polymorphisms to the inhibition of ADP-induced platelet aggregation by clopidogrel in healthy Chinese volunteers. 2. Eighteen healthy male volunteers (six CYP2C19*1/CYP2C19*1, six CYP2C19*1/CYP2C19*2and*3 and six CYP2C19*2/CYP2C19*2and*3) were enrolled in the study. Each subject took 300 mg clopidogrel on the first day and then 75 mg once daily for 2 consecutive days. Blood samples were taken to measure ADP-induced platelet aggregation at baseline and 4, 24 and 72 h after administration of the first dose of clopidogrel. 3. There were significant decrease in 2 and 5 micromol/L ADP-induced platelet aggregation at 4, 24 and 72 h after clopidogrel among the three CYP2C19 genotypes compared with baseline (P < 0.001). The change in 5 micromol/L ADP-induced platelet aggregation in subjects with the CYP2C19*1/CYP2C19*1 genotype was greater than that in subjects with the CYP2C19*2/CYP2C19*2and*3 genotype at 4 h (49.0 +/- 15.5 vs 29.7 +/- 17.4%, respectively; P = 0.029), 24 h (48.7 +/- 20.5 vs 25.0 +/- 17.6%, respectively; P = 0.035) and 72 h (45.5 +/- 15.2 vs 26.5 +/- 15.8%, respectively; P = 0.030) after clopidogrel administration. 4. In conclusion, CYP2C19*2 and CYP2C19*3 genetic polymorphisms reduced clopidogrel inhibition of ADP-induced platelet aggregation, with the degree of inhition dependent on the genetic polymorphism present.
authors.affiliation: Xiangya Hospital, Clinical Pharmacology Institute, Central South University, Changsha, China.
authors.forename: Bi-Lian
authors.initials: BL
authors.lastname: Chen
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Qing
authors.initials: Q
authors.lastname: Li
authors.forename: Ya-Lin
authors.initials: YL
authors.lastname: Li
authors.forename: Yi-Jing
authors.initials: YJ
authors.lastname: He
authors.forename: Lan
authors.initials: L
authors.lastname: Fan
authors.forename: Lian-Sheng
authors.initials: LS
authors.lastname: Wang
authors.forename: Zhao-Qian
authors.initials: ZQ
authors.lastname: Liu
authors.forename: Hong-Hao
authors.initials: HH
authors.lastname: Zhou
mesh_terms: D000244:Adenosine Diphosphate / Q000494:pharmacology*; D000328:Adult; D001189:Aryl Hydrocarbon Hydroxylases / Q000235:genetics*; D000077144:Clopidogrel; D065731:Cytochrome P-450 CYP2C19; D005838:Genotype; D006801:Humans; D008297:Male; D010974:Platelet Aggregation / Q000187:drug effects* / Q000235:genetics* / Q000502:physiology; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology*; D011110:Polymorphism, Genetic; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: D010975:Platelet Aggregation Inhibitors; D000244:Adenosine Diphosphate; D000077144:Clopidogrel; D001189:Aryl Hydrocarbon Hydroxylases; C045793:CYP2C19 protein, human; D065731:Cytochrome P-450 CYP2C19; D013988:Ticlopidine