PT  - JOURNAL ARTICLE
AU  - Ci, Lei
AU  - Kusuhara, Hiroyuki
AU  - Adachi, Masashi
AU  - Schuetz, John D.
AU  - Takeuchi, Kenji
AU  - Sugiyama, Yuichi
TI  - Involvement of MRP4 (<em>ABCC4</em>) in the Luminal Efflux of Ceftizoxime and Cefazolin in the Kidney
AID  - 10.1124/mol.106.031823
DP  - 2007 Jun 01
TA  - Molecular Pharmacology
PG  - 1591--1597
VI  - 71
IP  - 6
4099  - http://molpharm.aspetjournals.org/content/71/6/1591.short
4100  - http://molpharm.aspetjournals.org/content/71/6/1591.full
SO  - Mol Pharmacol2007 Jun 01; 71
AB  - The purpose of the present study was to investigate the role of multidrug resistance-associated protein 4 (MRP4) in the tubular secretion of cephalosporin antibiotics. Most of the injectable cephalosporins have an inhibitory effect on the ATP-dependent uptake of [3H]dehydroepiandrosterone sulfate by membrane vesicles expressing hMRP4, whereas cephaloridine, cefsulodin, and cefepime do not. Aminocephalosporins have a weak inhibitory effect. Significant ATP-dependent transport of ceftizoxime (Km, 18 μM), cefazolin (Km, 80 μM), cefotaxime, and cefmetazole has been observed only in the membrane vesicles expressing hMRP4. Ceftizoxime and cefazolin were given by a constant intravenous infusion to wild-type and Mrp4–/– mice. The steady-state plasma concentrations of ceftizoxime and cefazolin were unchanged in Mrp4–/– mice. The urinary recovery of ceftizoxime was significantly reduced in Mrp4–/– mice, whereas it was unchanged for cefazolin. The kidney-to-plasma concentration ratio of ceftizoxime and cefazolin was increased 2.0- and 2.7-fold in Mrp4–/– mice, respectively; thus, the renal clearance with regard to the kidney concentration was reduced in Mrp4–/– mice, to 7.5 and 34% of the corresponding control values, respectively. These results suggest that Mrp4 is involved in the tubular secretion of ceftizoxime and cefazolin, in concert with basolateral uptake transporters. The American Society for Pharmacology and Experimental Therapeutics