Tht change on kidney tissue antioxidant gene level of fluorosis rats

Objective The role of oxidative stress in mech-anism of kidney damage of chronic fluorosis rats was observed.Methods Rats were exposed to the water with fluoride for 3 months.The content of the uric acid(UA) and malondialdehyde(MDA) and the vitality of the antioxidant enzyme superoxide dismutase(SOD) and glutathione peroxidase(GSH-Px) in the serum were determined by the methods of biochemical assay.Total RNA was extracted from kidney tissue and the expression of mRNA of GSH-Px,SOD,thioredoxin(Trx) was determined in the kidney tissue by the methods of RT-PCR.Results The content of the GSH-Px,SOD and MDA were increased in serum when the rats were exposed to fluoride with normal diet and the rising of GSH-Px was statistical significance(P0.05).As compared with control group,the content of MDA in serum in group of low calcium and fluoride treated was significantly increased.As compared with the corresponding control group,the content of uric acid in serum in the normal diet 100 mg F-/L and low calcium 100 mg F-/L group was decreased.The content of GSH-Px,SOD and Trx at the level of mRNA were increased significantly and the gene expression of SOD was significant(P0.05) in the kidney tissue treated with fluoride.The level of gene expression of SOD was increased significantly in the kidney tissue in the low calcium control group either.Conclusions A certain concentration of fluoride stimulated the antioxidant enzyme gene expression in kidney.It was coincident that antioxidant enzyme activity increased in the serum.The oxidative stress should exacerbate when fluoride toxicity combined with low calcium.Uric acid might relieve oxidative stress caused by fluoride.