Ulinastatin provides protection against endotoxin-induced acute kidney injury in rats

Objective To explore the role of Ulinastatin (UTI) in lipopolysaccharide (LPS)-induced acute kidney injury (AKI) in rats. Methods Thirty male Wistar rats were randomized to receive caudal injection of 1 ml normal saline (control group), or 5 mg/kg LPS (LPS group) or 5 mg/kg LPS plus 105 U/kg UTI (LPS+UTI group). Six hours later, the blood and urine levels of IL-18 were determined with enzyme-linked immunosorbent assay (ELISA), serum creatinine (SCr) with Jaffe′s reaction and the morphology of kidneys observed under an electron microscope. Results The level of Scr was significantly elevated in the LPS group compared with normal controls and the LPS+UTI group, as were levels of blood and urine IL-18. Microscopically, the renal tubular epithelium in normal rats showed large and round-shaped nuclei, intact brush border and mitochondria, whereas pyknosis, rupture of mitochondrial cristae, vacuolization and disrupted microvilla were found for the LPS group in contrast to the nearly normal morphology in the LPS+UIT group except for sparsely identifiable resolution of mitochondrial cristae. Conclusion UTI may reduce the expression of pro-inflammatory IL-18, hence its protection against LPS-induced AKI in rats.