... adenosinetriphosphate (ATP), 4-aminopyridine, aprotinin, 1-chloro-2,4-dinitrobenzene, clotrimazole, creatine kinase, creatinephosphokinase, daunorubicin, dideoxyforskolin, iso-butylmethylxanthine ... range of inhibitors and substratesfor MRPs including MK-571, methotrexate, E217bG, and DNP-SG and also by glibenclamide and frusemide. Weshow that this cGMP exporter is distinct from MRP1 and has ... [9].Methotrexate and E217bG were found to inhibit thecGMP uptake in human erythrocyte vesicles with E217bGat 65 lMinhibiting about 90% and methotrexate inhi-biting about 75% at 275 lM and completely...