Efficacy of oral supplemental hydration for the prevention of contrast-induced nephropathy in rats

Purpose To compare oral rehydration solution (ORS) with saline infusion for preventing contrast-induced nephropathy (CIN) in a rat model. Materials and methods Adult male Sprague–Dawley rats (310–360 g) received intravenous indomethacin (10 mg/kg), N G -nitro- l -arginine methyl ester (10 mg/kg), and iohexol (10 mL/kg) to induce acute contrast-induced renal injury (CIN group); control rats received saline only. For hydration, rats received either continuous infusion (20 mL/kg/h) of saline or three oral doses (20 mL/kg each) of ORS. Acute renal injury was evaluated by assaying urine collected for 24 h beginning 2 h before the contrast injection, evaluating blood taken 22 h after the contrast injection, and examining the kidneys histopathologically. Results Hydration with saline prevented only the contrast-induced increase in plasma creatinine, whereas ORS prevented deleterious changes in plasma creatinine, blood urea nitrogen, and creatinine clearance as well as in urinary protein, albumin, and N -acetyl- d -glucosaminidase concentrations. Histopathologic changes noted in the CIN group were diminished in both saline and ORS groups. Conclusion Both intravenous saline administration and oral hydration with ORS decreased the severity of CIN. Hydration with ORS was comparable to intravenous saline infusion in preventing CIN-associated abnormalities.