First Prize: Isoprostane: Quantitation of Renal Ischemia and Reperfusion Injury After Renal Artery Clamping in an Animal Model

摘要

BACKGROUND AND PURPOSE: Laparoscopic and robotic partial nephrectomy involves temporary clamping of the renal artery, making the kidney susceptible to ischemic damage. Isoprostane represents one potential marker of oxidative injury. The objective was to determine if renal interstitial isoprostane levels can quantitate renal damage secondary to warm ischemia. A second goal is to investigate allopurinol for renoprotective abilities using this model. We chose to investigate potential renoprotection of allopurinol because previous studies have demonstrated transplant kidneys pretreated with allopurinol to have less damage from ischemia. MATERIALS AND METHODS: A microdialysis probe was inserted into the renal parenchyma of rats to allow continuous dialysis and collection of the effluent for isoprostane levels. After clamping of the renal vessels for predefined intervals of ischemia, the interstitial effluent from the probe was collected and subsequently analyzed for isoprostane levels with and without allopurinol pretreatment. RESULTS: Clamping of the renal artery and vein produced increases in isoprostane levels during the ischemic period and larger increases during reperfusion. There was a trend for increased postclamp isoprostane levels as clamp times increased. When comparing isoprostane levels in rats that did not receive allopurinol, there were significant differences between the clamp and postclamp levels of isoprostane, with allopurinol offering protection to the kidney from ischemic changes caused by clamping the renal hilum. CONCLUSIONS: Our data have demonstrated that isoprostane levels are a potential real-time marker of renal ischemia and reperfusion injury. We also found allopurinol administration demonstrated a trend toward renoprotective abilities in the hilar occluded kidney.