title: Measurement of the activity of multixenobiotic resistance mechanism in the common carp Cyprinus carpio.
abstract: The multixenobiotic resistance (MXR) mechanism, mediated by activity of the transmembrane P-glycoprotein, represents a basic biological defence system in aquatic organisms. Here we investigate the MXR transport activity in an aquatic vertebrate, the common carp (Cyprinus carpio). We measured the accumulation rate of a model MXR substrate, the fluorescent dye rhodamine B (RB), in gills, lateral muscles, liver and bile. Results obtained using this method showed a significant increase of RB accumulation in tissues of fish exposed for I h to 3 microM RB in the presence of the model MXR inhibitors cyclosporin A (CA, 5 microM) or verapamil (VER, 10 microM), when compared with specimens exposed without inhibitors. The highest increase in RB accumulation detected in the liver (VER 54%, CA 170%) indicates that among the tissues analysed within this study, liver is the most prominent candidate organ for the functional detection of MXR activity in C. carpio.
authors.affiliation: Department for Marine and Environmental Research, Rudjer Bosković Institute, Zagreb, Croatia. smital@rudjer.irb.hr
authors.forename: Tvrtko
authors.initials: T
authors.lastname: Smital
authors.forename: Roberta
authors.initials: R
authors.lastname: Sauerborn
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000494:pharmacology; D000818:Animals; D002347:Carps; D004396:Coloring Agents / Q000493:pharmacokinetics; D018432:Drug Resistance, Multiple; D005880:Gills / Q000737:chemistry; D008099:Liver / Q000737:chemistry; D018482:Muscle, Skeletal / Q000737:chemistry; D012235:Rhodamines / Q000493:pharmacokinetics; D014018:Tissue Distribution; D015262:Xenobiotics / Q000378:metabolism / Q000493:pharmacokinetics / Q000494:pharmacology*
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D004396:Coloring Agents; D012235:Rhodamines; D015262:Xenobiotics; C029773:rhodamine B