role of dl alphalipoic acid in gentamicin induced nephrotoxicity the effect of dl alphalipoic acid on the nephrotoxic potential of gentamicin was examined intraperitoneal injection of gentamicin 100 mgkgday to rats resulted in decreased activity of the glycolytic enzymeshexokinase phosphoglucoisomerase aldolase and lactate dehydrogenase the two gluconeogenic enzymesglucose6phosphatase and fructose16diphosphatase the transmembrane enzymes namely the na katpase ca2atpase mg2atpase and the brushborder enzyme alkaline phosphatase also showed decreased activities this decrease in the activities of atpases and alkaline phosphatase suggests basolateral and brush border membrane damage decreased activity of the tca cycle enzymes isocitrate dehydrogenase icdh succinate dehydrogenase sdh and malate dehydrogenase mdh suggests a loss in mitochondrial integrity these biochemical disturbances were effectively counteracted by lipoic acid administration lipoic acid administration by gastric intubation at two different concentrations 10 mg and 25 mgkgday brought about an increase in the activity of the glycolytic enzymes atpases and the tca cycle enzymes the gluconeogenic enzymes however showed a further decrease in their activities at both the concentrations of lipoic acid administered these observations shed light on the nephroprotective action of lipoic acid against experimental aminoglycoside toxicity and the protection afforded at 25 mgkgday of lipoic acid was noted to be higher than that at 10 mg level