关键词: 破骨细胞, 酒石酸盐类, 酸性磷酸酶, 明胶酶B, 大鼠, Wistar

Abstract: Objective To investigate the effects of excessive fluoride on osteoclastic activity in rats. Methods The tibia slices of chronic fluorotic rats were stained with HE and tartrate-resistant acid phosphatase (TRAP)，and the changes of osteoclasts were observed；At the same time，the protein was extracted from metaphysis of femurs in chronic fluorotic rats，then the expression of matrix metalloproteinase-9 (MMP-9) was investigated using Western blotting technique. Results The number of osteoclasts in tibia envelope and metaphysis increased in fluoride groups and compact bone of the cortex became porosity. Compared with stock diet group，the number of TRAP positive osteoclasts increased in stock diet group treated with fluoride， low calcium diet group，and low calcium diet group treated with fluoride. But there was no much statistical difference (P>0.05). Compared with stock diet group, the increase of MMP-9 expression in stock diet group treated with fluoride was statistically significant(P<0.05). Statistical difference also showed between low calcium diet group and low calcium diet group treated with fluoride (P<0.05)，and there were significant diffiences when both above were compared with stock diet group (P<0.05). Conclusion The results prove that excessive fluoride can induce accelerative bone turnover and active bone resorption, and low calcium diet is an important promotive factor of skeletal fluorosis. Fluoride can enhance the activity of osteoclastic resorption by increasing the expression of MMP-9.

Key words: osteoclasts, tartrates, acid phosphatase, gelatinase B, rats, Wistar