Warm ischemia is a potential problem during the harvesting of cadaveric kidneys for transplantation purposes. This ischemia can cause impaired renal function following transplantation. The purpose of our study was to determine whether the beta-adrenergic blocking agent propranolol was effective in improving renal function after ischemia. Dog kidneys were subjected to 30 minutes of warm ischemia followed by hypothermic pulsatile preservation for 24 hours. The kidneys then were autotransplanted with immediate contralateral nephrectomy. In this model only 50% of the untreated control group survived. Three different protocols using propranolol were tested. Administration of propranolol to dogs before the ischemic period, or installation of propranolol into the renal artery at the start of the ischemia, or addition of propranolol to the preservation perfusate lessened the severity of acute tubular necrosis and resulted in 100% long-term survival. Although the mechanism was not investigated, it has been suggested that propranolol is acting through its blockade of beta-mediated renin release and/or through its so-called membrane-stabilizing effect.