Remote renal injury following partial hepatic ischemia/reperfusion injury in rats

Liver ischemia/reperfusion has been shown to result in injury of remote organs such as the heart and lungs. Whether or not acute liver injury also results in kidney injury has so far not been adequately addressed. In anesthetized Wistar rats, partial (70%) normothermic hepatic ischemia was applied for 75 min. After 24 h of reperfusion, renal injury was assessed by histology, creatinine and blood urea nitrogen (BUN) serum concentrations, renal expression of proinflammatory genes [quantitative real-time polymerase chain reaction (qRT-PCR)], caspase-3 activation (Western blot), and neutrophil accumulation (myeloperoxidase assay). Twenty-four hours after hepatic ischemia, creatinine (0.57+/-0.06 vs. 0.32+/-0.04 mg/dL) and BUN (40.7+/-15.3 vs. 14.3+/-2.0 mg/dL) were increased when compared to sham. qRT-PCR revealed higher renal intercellular adhesion molecule-1 gene expression following hepatic ischemia (166+/-45% when compared to sham) but no differences in renal monocyte chemoattractant protein-1, macrophage inflammatory protein-2, and inducible NO synthase expression. In both groups, kidneys showed no morphological damage and no increase in caspase-3 and myeloperoxidase activity. Severe hepatic ischemia results in a moderate impairment of renal function in rats but does not trigger an inflammatory response in the kidney and does not result in morphological damage of the kidney.