代谢
有人提出,非洛地平相较于其药物类别中的其他成员,不太可能受到首过效应的影响,并且其二氢吡啶环主要在侧链代谢后进行氧化。非洛地平具有高度亲脂性,这使得它能够进入富含磷脂的细胞膜,并到达钙通道靶点的二氢吡啶结合位点。非洛地平主要在肝脏中代谢。其代谢产物包括去苯基非洛地平(DPH)、脱氨非洛地平(AL)和去苄基非洛地平(DBZ)。这些代谢产物都表现为钙通道拮抗剂。在一项研究中,DBZ和DPH的血管舒张能力分别约为未代谢药物的三分之二和三分之一。研究表明,口服非洛地平氢氯酸盐后的大多数药理效应归功于未改变的药物,其代谢产物在其治疗效应中起的作用很小。在一项对六名健康志愿者的研究中,尿液中未发现显著量的未改变药物。在口服非洛地平后24小时内收集的尿液中,剂量的1.1%以脱氨非洛地平的形式排出,0.5%以脱氨非洛地平的吡啶类似物形式排出。
It has been suggested that efonidipine is less likely to be subject to the first-pass than other members of its drug class, and and that its dihydropyridine ring is oxidized primarily after metabolism of the side chain. Efonidipine is highly lipophilic and this allows for its entry into the phospholipid-rich cell membrane and reach the dihydropyridine binding site of the calcium channel targets. Efonidipine is mainly metabolized in the liver. Its metabolites are N-dephenylated Efonidipine (DPH), deaminated efonidipine (AL) and N-debenzylated Efonidipine (DBZ). Both metabolites behave as calcium antagonists. In one study, the vasodilating capabilities of DBZ and DPH were about two-thirds and one-third respectively than that of the unmetabolized drug. Research suggests that the majority of the pharmacological effect after oral dosing of efonidipine hydrochloride is due to unchanged drug and its metabolites play little role in its therapeutic effect. In a study of six healthy volunteers, no significant amount of unchanged drug was excreted in urine. The urine samples collected for 24 h after oral efonidipine administration, 1.1% of the dose was excreted as deaminated-efonidipine, and 0.5% as a pyridine analogue of deaminated-efonidipine.
来源:DrugBank