Effects of fluoride on ultrastructure of thyroids in rats / 中国地方病学杂志

ABSTRACT

Objeetive To investigate the effects of fluoride on ultra-structure of thyroid in rats.Methods Eighty SD rats were randomly divided into 4 groups,20 rats in each group.One was control group,the other tree groups were respectively administered 1.19×10-3 mol/L(LF),2.38×10-3 mol/L(MF),and 4.76×10-3 mol/L(HF) of sodium fluoride in drinking water,respectively.The total feeding experiment lasted 1 50 days.Thyroid tissues of rats were collected and ultra-thin sections were made and thyroid ultra-structure wa8 observed under electronic microscope.Results In LF group,nuclear pycnosis and cell vacuolization were observed.In MF group,the electron density decreased,and mitochondria reduced in number.In HF group,some mitochondria were Seen swelling,colloid of thyroid follicles aecumulated,the electronic density in this site increased,microvilli of thyroid endothelial cells decreased significantly,and the amount of lysosome significantly increased.In MF and HF group,organelle disordered,vacuolization in cell endoplasm appeared,membranes of rough endoplasmic reticulum(RER)broke,ribosomes ablated,mitochondria swollen and vacuolated,some cristaes of mitochondria disrupted or disappeared.Conclusion Fluoride can damage the ultra-structure of thyroid,especially the bio-membranes of thyroid cells.