Renal purine efflux and xanthine oxidase activity during experimental nephrosis in rats: Difference between puromycin aminonucleoside and adriamycin nephrosis

1. The hypothesis was tested that the renal xanthine oxidase system provides a source of oxygen free radicals in puromycin aminonucleoside and adriamycin experimental nephroisis by generating uric acid from hypoxanthine and xanthine. 2. The concentrations in renal tissue of the putative intermediary products of puromycin aminonucleoside metabolism, hypoxanthine and xanthine, and of their precursors, adenosine and inosine, were lower in rats treated with puromycin aminonucleoside than in normal controls, whereas concentrations of the metabolites were normal after adriamycin intoxication. Their daily urinary excretion was lower in the 24 h after puromycin aminonucleoside administration compared with the baseline values and returned to near normal levels within 5 days. After adriamycin the 24 h urinary excretion of xanthine and uric acid was double the baseline levels (P