The role of oxygen free radicals and prostaglandins in reperfusion injury to warm ischemic kidneys.

The present study was designed to determine whether the administration of superoxide dismutase (SOD) can alleviate ischemic kidney damage and whether there is a relationship between oxygen free radicals and thromboxane (Tx). In 17 dogs, the right kidney was removed and the vascular pedicle of the left kidney was clamped for 75 min. Prior to reperfusion, the ischemic kidney was rinsed with 5 mg SOD and an additional 20 mg SOD was infused systemically. Blood samples were drawn from the renal vein before ischemia and after reperfusion to determine serum levels of thromboxane B2 (TxB2). All eight untreated dogs died within 1 week of renal failure, and the nine treated dogs demonstrated transient renal failure, with a significant difference (P less than 0.001) being found between the two groups. A significant difference (P less than 0.001) in TxB2 levels was found in the untreated dogs before and after ischemia and between the two groups following reperfusion. Animals that are treated with SOD after the ischemic event has occurred but before reperfusion exhibit a favorable clinical course in terms of survival and renal function. Tx synthesis in the kidney can be blocked by the administration of SOD.