title: Elevated systemic elimination of cimetidine in rats with acute biliary obstruction: the role of renal organic cation transporter OCT2.
abstract: Renal tubular secretion of cationic drugs is dominated by two classes of organic cation transporters, OCT2/SLC22A2 and MATE1/SLC47A1, localized to the basolateral and brush-border membranes of the renal tubular epithelial cells, respectively. However, little is known about the expression and function of these transporters in acute cholestasis. Systemic clearance of cimetidine was significantly higher in rats with bile duct ligation (BDL) for 24 hours than in sham-operated rats, with no significant changes in the volume of distribution between the groups. In addition, net tubular secretory clearance of cimetidine was significantly higher in the BDL rats compared with the sham rats, with no significant changes in the glomerular filtration rate. Moreover, the renal tissue-to-plasma concentration ratio of cimetidine was elevated in BDL rats, although the renal tissue-to-urine clearance ratio of cimetidine was not different between the two groups. The expression level of basolateral organic cation transporter rOCT2 protein in the kidney cortex was markedly higher in BDL rats than that in the sham rats, but that of H+/organic cation antiporter rMATE1 protein in the brush-border membranes was not significantly different between the two groups. These results demonstrate that the renal tubular secretion of cimetidine was increased by acute cholestasis, and this increase was attributable to elevated expression levels of rOCT2 but not of rMATE1 in the rat.
authors.affiliation: Department of Clinical Pharmacy and Biopharmaceutics, Mie University Graduate School of Medicine, Tsu, Mie, Japan.
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Kurata
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Muraki
authors.forename: Hideki
authors.initials: H
authors.lastname: Mizutani
authors.forename: Takuya
authors.initials: T
authors.lastname: Iwamoto
authors.forename: Masahiro
authors.initials: M
authors.lastname: Okuda
mesh_terms: D000208:Acute Disease; D000818:Animals; D017920:Antiporters / Q000032:analysis; D050482:Catecholamine Plasma Membrane Transport Proteins / Q000032:analysis; D002779:Cholestasis / Q000378:metabolism; D002927:Cimetidine / Q000493:pharmacokinetics*; D006635:Histamine H2 Antagonists / Q000493:pharmacokinetics*; D007668:Kidney / Q000378:metabolism*; D008297:Male; D008657:Metabolic Clearance Rate; D027701:Organic Cation Transport Proteins / Q000032:analysis / Q000502:physiology*; D000075102:Organic Cation Transporter 2; D051381:Rats; D017208:Rats, Wistar; D013739:Testosterone / Q000097:blood
chemical_list: D017920:Antiporters; D050482:Catecholamine Plasma Membrane Transport Proteins; D006635:Histamine H2 Antagonists; D027701:Organic Cation Transport Proteins; D000075102:Organic Cation Transporter 2; C493212:Slc22a1 protein, rat; C100590:Slc22a2 protein, rat; C515734:Slc47a1 protein, rat; D013739:Testosterone; D002927:Cimetidine