Oat5 and NaDC1 Protein Abundance in Kidney and Urine After Renal Ischemic Reperfusion Injury

The aim of this study was to evaluate the abundance of the organic anion transporter 5 (Oats) and the sodium-dicarboxylate cotransporter 1 (NaDC1) in kidney and urine after renal ischemic reperfusion injury. Renal injury was induced in male Wistar rats by occlusion of both renal pedicles for 0 (Group Sham), 5 (Group 151160), or 60 (Group 1601160) min. The studies were performed after 60 min of reperfusion. The expression of Oats and NaDC1 was evaluated by IHC and Western blotting. Oats and NaDC1 abundance and alkaline phosphatase activity (AP) were assayed in urine. A decreased expression in renal homogenates and apical membranes and an increase in urinary excretion of Oats and NaDC1 were observed in I60R60 rats, as well as alterations of other widely used parameters for renal dysfunction and injury (plasma creatinine, urinary AP activity, kidney weight, histological lesions). In contrast, in the I5R60 group, only an increase in urinary excretion of Oats and mild histopathological damage was detected. This is the first study on Oats and NaDC1 detection in urine. These results suggest that urinary excretion of Oats might be an early indicator of renal dysfunction, which is useful for detection of even minor alterations in renal structural and functional integrity. (J Histochem Cytochem 57:17-27, 2009)