[Glomerulonephritis and superoxide dismutase].

To study the role of reactive oxygen species (ROS) in chronic renal disease, we studied the localization of Cu, Zn-superoxide dismutase (SOD) in glomeruli of patients with IgA nephropathy by immunohistochemistry on 37 kidney specimens consisting of 32 IgA nephropathy and normal parts of the 5 resected kidneys with renal tumors serving as controls. To evaluate the change in renal function, creatinine clearance (Ccr) was assessed at the time of biopsy and 1 year after the biopsy. In the normal kidney, Cu, Zn-SOD was localized in the tubular cells, and not in the glomeruli. In the kidney with IgA nephropathy, Cu, Zn-SOD was detected on the epithelial side of the glomerular capillary wall in addition to the tubular cells. The extent of localization of this enzyme was compared with the clinical findings at the time of biopsy. When Cu, Zn-SOD was stained strongly in the glomeruli, the histological change of the glomeruli was milder, and the renal function appeared to be more preserved; the decrease in Ccr one year after the renal biopsy was inhibited. These findings suggest that Cu, Zn-SOD has beneficial actions for renal function as anti-oxidative factors.