title: Effects of chronic renal failure on kidney drug transporters and cytochrome P450 in rats.
abstract: Chronic renal failure (CRF) leads to decreased drug renal clearance due to a reduction in the glomerular filtration rate. However, little is known about how renal failure affects renal metabolism and elimination of drugs. Because both depend on the activity of uptake and efflux by renal transporters as well as enzymes in tubular cells, the purpose of this study was to investigate the effects of CRF on the expression and activity of select renal drug transporters and cytochrome P450. Two groups of rats were studied: control and CRF (induced by 5/6 nephrectomy). Compared with control rats, we observed reductions in the expression of both protein and mRNA of Cyp1a, sodium-dependent phosphate transport protein 1, organic anion transporter (Oat)1, 2, and 3, OatK1/K2, organic anion-transporting polypeptide (Oatp)1 and 4c1, P-glycoprotein, and urate transporter 1, whereas an induction in the protein and mRNA expression of Mrp2, 3, and 4 and Oatp2 and 3 was observed. Cyp3a expression remained unchanged. Similar results were obtained by incubating a human proximal tubule cell line (human kidney-2) with sera from CRF rats, suggesting the presence of uremic modulators. Finally, the renal elimination of [(3)H]digoxin and [(14)C]benzylpenicillin was decreased in CRF rats, compared with controls, as shown by a 4- and 9-fold accumulation, respectively, of these drugs in kidneys of rats in CRF. Our results demonstrate that CRF affects the expression and activity of several kidney drug transporters leading to the intrarenal accumulation of drugs and reduced renal clearance that could, at least partially, explain the tubular toxicity of many drugs.
authors.affiliation: Service de Néphrologie et Centre de Recherche de l’Hôpital Maisonneuve-Rosemont, Montréal, Québec, Canada.
authors.forename: Judith
authors.initials: J
authors.lastname: Naud
authors.forename: Josée
authors.initials: J
authors.lastname: Michaud
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Beauchemin
authors.forename: Marie-Josée
authors.initials: MJ
authors.lastname: Hébert
authors.forename: Michel
authors.initials: M
authors.lastname: Roger
authors.forename: Stéphane
authors.initials: S
authors.lastname: Lefrancois
authors.forename: Francois A
authors.initials: FA
authors.lastname: Leblond
authors.forename: Vincent
authors.initials: V
authors.lastname: Pichette
mesh_terms: D000818:Animals; D001692:Biological Transport; D015153:Blotting, Western; D002460:Cell Line; D003470:Culture Media; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D004195:Disease Models, Animal; D015870:Gene Expression; D006801:Humans; D007668:Kidney / Q000201:enzymology / Q000378:metabolism*; D007676:Kidney Failure, Chronic / Q000201:enzymology / Q000378:metabolism* / Q000503:physiopathology; D007677:Kidney Function Tests; D007687:Kidney Tubules, Proximal / Q000166:cytology / Q000378:metabolism; D008297:Male; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D004364:Pharmaceutical Preparations / Q000097:blood / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D020112:Rhodamine 123 / Q000097:blood / Q000493:pharmacokinetics; D014511:Uremia / Q000097:blood / Q000378:metabolism
chemical_list: D003470:Culture Media; D026901:Membrane Transport Proteins; D004364:Pharmaceutical Preparations; D012333:RNA, Messenger; D020112:Rhodamine 123; D003577:Cytochrome P-450 Enzyme System