Endotoxin-induced alterations in renal function with particular reference to tubular enzyme activity.

This study was designed to evaluate the effects of endotoxin infusion (0.25 mg/kg) over a 4-hr period on renal function and tubular enzyme activity. Endotoxin administration resulted in a decrease in blood pressure, osmolar clearance, and creatinine clearance (P less than 0.05). The enzyme activities of alkaline phosphatase (ALP) and lactic dehydrogenase (LDH) in the urine increased, as did the serum creatinine (P less than 0.05). There were no significant changes in the renal artery flow, urinary output, heart rate, serum electrolytes, and serum enzyme activities. In contrast, in the saline control group, the renal artery flow increased (P less than 0.05), whereas the serum creatinine, urinary ALP, and urinary LDH decreased over time. All other parameters remained relatively stable. These data suggest that an increase in urinary enzyme activity reflects compromised renal function and is independent of the renal artery flow. This may have clinical application in detecting early renal damage due to endotoxemia or sepsis.