OBJECTIVETo investigate the effects of oxymatrine on the expression of nuclear factor kappa B (NF-kappaB) in the kidneys of rats with adriamycin-induced chronic renal fibrosis.

METHODSTotally 120 Wistar rats were randomly assigned to normal control group, renal fibrosis model group, benazepril treatment group and oxymatrine treatment group (n=30). The rats in the normal control were injected with normal saline via the tail vein, and those in the other 3 groups with adriamycin (2 mg/kg) on the 7th day and 21st day of the experiment, respectively. Oxymatrine (100 mg/kg) or benazepril (6 mg/kg) was given by gastric perfusion after the second injection. Every 4 weeks after the second injection, 5 rats in each group were killed to evaluate the pathological changes and functional impairment of the kidney. Immunohistochemistry was used to detect the expression of NF-kappaB and inhibitory kappa B (IkappaB) in the kidney. The association of NF-kappaB expression with IkappaB expression, renal pathological changes and functional impairment were studied.

RESULTSOxymatrine and benazepril ameliorated renal fibrosis and functional impairment. Immunohistochemical staining revealed increased NF-kappaB expression and decreased IkappaB expression in the model group in comparison with oxymatrine and benazepril treatment groups 8 weeks after the second injection, but no significant difference was noted between the latter two groups. NF-kappaB expression in the kidneys of rats with adriamycin-induced chronic renal fibrosis showed an inverse correlation with IkappaB expression and positive correlation with pathological changes and functional impairment.

CONCLUSIONOxymatrine may inhibit renal fibrosis by down-regulating NF-kappaB expression, which may play a key role in protection against renal fibrosis.