Glycerol or fructose (40 mM) was added to the control perfusate and renal function was observed in the isolated perfused rat kidney during nonischemic perfusions or perfusions following 30 min of clamp ischemia. Addition of glycerol or fructose resulted in lowering adenosine triphosphate (ATP) levels to 62 and 35%, respectively, of levels achieved with control perfusate under nonischemic conditions (p less than 0.01). Total adenine nucleotides (TAN) were also lowered to 67% with glycerol and 61% with fructose of control values under nonischemic conditions (p less than 0.05). However, physiologic parameters of renal plasma flow and inulin clearance were essentially unaffected by either glycerol or fructose. Following ischemia, glycerol and fructose reduced ATP levels to 51 and 37% and TAN levels to 67 and 65%, respectively, of values seen with control perfusate. However, recovery of renal plasma flow and inulin clearance were uneffected by the addition of either glycerol or fructose. Thus, a 33-65% reduction in renal tissue ATP by glycerol or fructose does not appear to have a deleterious effect on organ function in the basal state or during recovery from an ischemic insult in the isolated perfused rat kidney.