ticlopidine. Inhibition was attenuated by the presence of alternative active site ligands but not by nucleophilic trapping agents or reactive oxygen scavengers, further supporting mechanism-based action. A chemical mechanism is discussed based on the known metabolic activation of clopidogrel and on the finding that hemoprotein integrity of recombinant CYP2B6 was not affected by irreversible inhibition. These
噻吩并
吡啶衍生物噻氯匹定和
氯吡格雷是
ADP诱导的血小板聚集的
抑制剂。这些前药的药理活性取决于细胞色素P450(P450)依赖
氧化为活性抗血栓形成剂。在这项研究中,我们通过使用人肝微粒体和
重组表达的P450亚型研究了
氯吡格雷和
噻氯匹定的相互作用潜力。
氯吡格雷和
噻氯匹定均以最高的效价抑制CYP2B6,以较低的效价抑制CYP2C19。
氯吡格雷也抑制CYP2C9,
噻氯匹定也抑制CYP1A2,效力较低。CYP2B6的抑制作用是时间和浓度依赖性的,并且如透析实验所示,它是不可逆的并且依赖于
NADPH,表明是基于机理的作用方式。灭活是非伪一阶类型,在微粒体(
重组CYP2B6)中
氯吡格雷和
噻氯匹定的最大灭活率(K(inact))为0.35(1.5 min(-1))和0.5 min(-1)(0.8 min(- 1)),
氯吡格雷的最大灭活剂浓度(KI)分别为0.5 microM(1.1 microM)和
噻氯匹定为0