Optivia Biotechnology, Menlo Park, CA 94025, USA.
Anal Biochem. 2010 Oct 1;405(1):50-8. doi: 10.1016/j.ab.2010.06.012. Epub 2010 Jun 9.
Hepatic disposition plays a significant role in the pharmacokinetics and pharmacodynamics of a variety of drugs. Sinusoidal membrane transporters have been shown to participate in the hepatic disposition of many pharmaceuticals. Two sinusoidal membrane transporters with an established role in hepatic disposition are OATP1B1 and OATP1B3 (organic anion-transporting polypeptides 1B1 and 1B3, respectively). OATP1B1 and OATP1B3 have been implicated in the hepatic uptake of statin drugs, and polymorphisms linked to OATP1B1 have been associated with deleterious patient endpoints. As a result, OATP1B1 and OATP1B3 represent sites for potential drug-drug interactions. Numerous methods exist for identifying potential drug-drug interactions with transporters. However, relatively few offer the convenience and speed of fluorescence-based assays. Here a fluorescence-based assay was developed for measuring the OATP1B1- and OATP1B3-mediated transport of 8-fluorescein-cAMP (8-FcA). The OATP1B1- and OATP1B3-mediated transport of 8-FcA was time dependent and saturable (K(m)=2.9 and 1.8 microM, V(max)=0.20 and 0.33 pmol/min/cm(2), respectively). Molecules known to interact with OATPs, including cyclosporin A, rifampicin, and glibenclamide, each demonstrated concentration-dependent inhibition of 8-FcA transport by OATP1B1 and OATP1B3. The in vitro fluorescence-based assays described here using 8-FcA as the substrate are convenient and rapid and have utility in screening drug candidates for potential drug-drug interactions with OATP1B1 and OATP1B3.
肝脏处置在多种药物的药代动力学和药效动力学中起着重要作用。已经表明，窦状膜转运体参与许多药物的肝脏处置。两种在肝脏处置中具有既定作用的窦状膜转运体是 OATP1B1 和 OATP1B3（分别为有机阴离子转运多肽 1B1 和 1B3）。OATP1B1 和 OATP1B3 被认为与他汀类药物的肝脏摄取有关，与 OATP1B1 相关的多态性与有害的患者终点相关。因此，OATP1B1 和 OATP1B3 代表潜在药物相互作用的部位。有许多方法可用于鉴定与转运蛋白的潜在药物相互作用。然而，相对较少的方法具有基于荧光的测定法的便利性和速度。这里开发了一种基于荧光的测定法，用于测量 OATP1B1 和 OATP1B3 介导的 8-荧光素-cAMP（8-FcA）的转运。8-FcA 的 OATP1B1 和 OATP1B3 介导的转运是时间依赖性和饱和的（K(m)=2.9 和 1.8 microM，V(max)=0.20 和 0.33 pmol/min/cm(2)，分别）。已知与 OATPs 相互作用的分子，包括环孢素 A、利福平、和格列本脲，每种都显示出对 OATP1B1 和 OATP1B3 介导的 8-FcA 转运的浓度依赖性抑制。此处描述的使用 8-FcA 作为底物的体外荧光测定法方便且快速，可用于筛选候选药物，以确定与 OATP1B1 和 OATP1B3 的潜在药物相互作用。
