Abstract

To investigate the mechanism of goiter caused by fluoride, goiter model of SD rats was produced by administering sodium fluoride in drinking water. Histological section of thyroid gland was made, and inducible nitric oxide synthase (iNOS) and vessel endothelial growth factor (VEGF) were determined by RT-PCR. Results showed that the capillary vessels in thyroid glands of the rats treated with fluoride proliferated and an obvious nodular goiter occurred in the fluoride-treated rats. Compared with the control, the contents of iNOS and VEGF in the thyroid glands of the rats with fluorosis was increased significantly (P0.05). It was concluded from the results that the mechanism of goiter caused by fluoride was that fluoride induced the over-expressions of iNOS and VEGF mRNAs in thyroid gland, which caused hyperplasia of capillary vessels.

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