Rat macrophages in experimental IgA nephropathy

To test whether the peripheral macrophage functions as early index of oxygen free radical release in association with the development of IgA nephropathy (IgAN), we studied female Lewis rats. IgAN was produced by treatment over 8 weeks with 0.1% bovine gamma globulin (BGG) in drinking water, followed by three daily intravenous injections of BGG, 1 mg/dose. Fifteen rats were divided randomly into three groups: control, IgAN, and IgAN fed vitamin E 100 IU/kg chow. At the end of the treatment period, rats were placed in individual metabolic cages for 24-h urine collections and then anesthetized with Inactin (100 mg/kg BW) for aspiration of peritoneal macrophages. The results (mean +/- SD) extended our previous data in male rats, confirming that the elevated proteinuria of IgAN (3.62 +/- 0.79 mg/day) was significantly reduced with vitamin E treatment (2.59 +/- 0.28 mg/day) in female rats (P < 0.002) More importantly, we indicated for the first time that oxygen free radicals production by peritoneal macrophages in IgAN was significantly reduced by vitamin E: 1.58 +/- 0.91 nmol/10(6) cells/15 min in the untreated group vs 3.28 +/- 0.54 nmol/10(6) cells/15 min in the vitamin E-treated group (P < 0.05).