Bachmeier Corbin J, Miller Donald W
Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, Nebraska 68198, USA.
Pharm Res. 2005 Jan;22(1):113-21. doi: 10.1007/s11095-004-9016-0.
To examine the capability of a fluorometric assay to identify and characterize the drug efflux interactions of a broad spectrum of drug agents in an in vitro model of the blood-brain barrier (BBB).
Various concentrations of drug agent (1, 10, and 100 microM) were evaluated for their effect on the cellular accumulation of the P-glycoprotein (P-gp) probe R123 (3.2 microM), and the mixed P-gp and multidrug resistance-associated protein (MRP) probe, BCECF (1 microM), in bovine brain microvessel endothelial cell (BBMEC) monolayers. Drugs demonstrating a significant effect were further quantitated using an expanded concentration range and a nonlinear regression curve fit to determine the potency (IC50) and efficacy (Imax) of the drug for P-gp and/or MRP.
Several of the 36 therapeutic agents examined showed drug efflux transporter interactions in BBMEC monlayers. Melphalan and risperidone significantly enhanced the accumulation of R123 over control (1.47- and 1.82-fold, respectively) with resulting IC50s of 1.4 and 14.6 microM, respectively. Chlorambucil and valproic acid significantly enhanced the accumulation of BCECF compared to control monolayers (2.02- and 4.01-fold, respectively) with resulting IC50s of 146.1 and 768.5 microM, respectively.
The current study demonstrates the feasibility of a fluorometric assay consisting of R123 and BCECF in assessing the drug efflux interactions of a variety of drugs in the BBB.
在血脑屏障（BBB）的体外模型中，研究一种荧光测定法识别和表征广谱药物的药物外排相互作用的能力。
评估不同浓度的药物制剂（1、10和100微摩尔）对牛脑微血管内皮细胞（BBMEC）单层中P-糖蛋白（P-gp）探针R123（3.2微摩尔）和P-gp与多药耐药相关蛋白（MRP）混合探针BCECF（1微摩尔）细胞积累的影响。对显示出显著影响的药物，使用扩展的浓度范围和非线性回归曲线拟合进一步定量，以确定该药物对P-gp和/或MRP的效力（IC50）和功效（Imax）。
所检测 的36种治疗药物中有几种在BBMEC单层中显示出药物外排转运体相互作用。美法仑和利培酮使R123的积累量比对照组显著增加（分别为1.47倍和1.82倍），IC50分别为1.4和14.6微摩尔。与对照单层相比，苯丁酸氮芥和丙戊酸使BCECF的积累量显著增加（分别为2.02倍和4.01倍），IC50分别为146.1和768.5微摩尔。
本研究证明了由R123和BCECF组成的荧光测定法在评估BBB中多种药物的药物外排相互作用方面的可行性。
