Involvement of superoxide and/or nitric oxide in renal tissue injury

We examined the influence of superoxide (O2-) and/or nitric oxide (NO) on renal tissue injury estimated from the levels of lipid peroxidation and sulfhydryl (SH) oxidation. Pyrogallol, an O2- generator and precursor of hydrogen peroxide, produced marked tissue injury, but this was prevented by superoxide dismutase (SOD)/catalase (CAT). Hemoglobin (Hb), a NO scavenger, provided protection from tissue injury caused by sodium nitroprusside (SNP). The tissue injury produced by 3-morpholinosydnonimine (SIN-1), which is thought to form peroxynitrite (ONOO-) as a simultaneous O2- and NO generator, was blocked by SOD/CAT or Hb. On the other hand, protein-SH and nonprotein-SH were significantly increased by addition of SOD/CAT or Hb. These data suggest that the renal tissue injury induced by O2-, NO and ONOO- can be blocked by SH, suggesting an important protective role against these reactive oxygen species in the mechanism of tissue defense.