title: Modulation of rhodamine 123 uptake by nigericin in sensitive and multidrug resistant leukemic cells.
abstract: We have investigated the effect of the ionophore nigericin (NIG) in multidrug resistant (MDR) cells, using intracellular accumulation of the fluorescent dye rhodamine 123 (R123). NIG increased the accumulation of R123 in half of the murine MDR RFLC3 population but not in the human MDR CEM/VLB 100 cells. Co-treatment of RFLC3 with NIG plus verapamil showed additive effect on the accumulation of R123. The increase in R123 accumulation observed in RFLC3 was not the consequence of a direct effect of NIG on P-glycoprotein and was accompanied by a redistribution of the dye throughout the cell and a high cytotoxicity, which prevents the use of NIG as a resistance modulating agent.
authors.affiliation: Laboratoire de Chimie-Physique, Université de Perpignan, France.
authors.forename: Y
authors.initials: Y
authors.lastname: Canitrot
authors.forename: D
authors.initials: D
authors.lastname: Lautier
authors.forename: P
authors.initials: P
authors.lastname: Viallet
authors.forename: J M
authors.initials: JM
authors.lastname: Salmon
mesh_terms: D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000493:pharmacokinetics*; D004317:Doxorubicin / Q000494:pharmacology / Q000633:toxicity; D004347:Drug Interactions; D004351:Drug Resistance; D004354:Drug Screening Assays, Antitumor; D005622:Friend murine leukemia virus; D006801:Humans; D007425:Intracellular Membranes / Q000187:drug effects / Q000502:physiology; D007938:Leukemia / Q000188:drug therapy* / Q000378:metabolism*; D004915:Leukemia, Erythroblastic, Acute / Q000188:drug therapy / Q000378:metabolism / Q000382:microbiology; D008564:Membrane Potentials / Q000187:drug effects; D051379:Mice; D008928:Mitochondria / Q000187:drug effects / Q000502:physiology; D009550:Nigericin / Q000494:pharmacology*; D010641:Phenotype; D020112:Rhodamine 123; D012235:Rhodamines / Q000493:pharmacokinetics*; D014407:Tumor Cells, Cultured / Q000187:drug effects; D014412:Tumor Virus Infections / Q000382:microbiology; D014700:Verapamil / Q000494:pharmacology; D014747:Vinblastine / Q000494:pharmacology / Q000633:toxicity
chemical_list: D000964:Antimetabolites, Antineoplastic; D012235:Rhodamines; D020112:Rhodamine 123; D014747:Vinblastine; D004317:Doxorubicin; D014700:Verapamil; D009550:Nigericin