title: ABC transporter function and regulation at the blood-spinal cord barrier.
abstract: We present here an initial characterization of ATP binding cassette (ABC) transporter function and regulation at the blood-spinal cord barrier. We isolated capillaries from rat spinal cords and studied transport function using a confocal microscopy-based assay and protein expression using western blots. These capillaries exhibited transport function and protein expression of P-glycoprotein (Abcb1), multidrug resistance protein 2 (Mrp2, Abcc2), and breast cancer-related protein (Bcrp, Abcg2). Exposing isolated capillaries to dioxin (activates aryl hydrocarbon receptor) increased transport mediated by all three transporters. Brain and spinal cord capillaries from dioxin-dosed rats exhibited increased P-glycoprotein-mediated transport and increased protein expression for all three ABC transporters. These findings indicate similar ABC transporter expression, function, and regulation at the blood-spinal cord and blood-brain barriers.
authors.affiliation: Laboratory of Toxicology and Pharmacology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709, USA.
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Campos
authors.forename: Christian
authors.initials: C
authors.lastname: Schröter
authors.forename: Xueqian
authors.initials: X
authors.lastname: Wang
authors.forename: David S
authors.initials: DS
authors.lastname: Miller
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B / Q000235:genetics / Q000378:metabolism; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism; D000818:Animals; D001692:Biological Transport; D001812:Blood-Brain Barrier / Q000378:metabolism*; D015153:Blotting, Western; D002196:Capillaries / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D024202:Electrophoretic Mobility Shift Assay; D008024:Ligands; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D018613:Microscopy, Confocal; D000072317:Polychlorinated Dibenzodioxins / Q000493:pharmacokinetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000098:blood supply* / Q000378:metabolism*; D015262:Xenobiotics / Q000493:pharmacokinetics
chemical_list: D018435:ATP Binding Cassette Transporter, Subfamily B; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters; C423013:Abcc2 protein, rat; C489249:Abcg2 protein, rat; D008024:Ligands; D000072317:Polychlorinated Dibenzodioxins; D015262:Xenobiotics; C095122:multidrug resistance protein 3