燃煤型氟中毒对大鼠骨骼组织形态计量学影响

Morphological changes of bone in progress of coal-burning fluorosis of rat

目的探讨燃煤型氟中毒对大鼠骨组织形态计量学影响。方法建立低蛋白低钙条件下燃煤型氟中毒大鼠模型;测定大鼠24 h尿氟、骨氟,根据氟斑牙判断损伤程度;采用X线骨密度仪测定大鼠股骨及胫骨骨密度;扫描电子显微镜下观察大鼠股骨松质骨超微结构的形态学改变,观察大鼠胫骨上端骨形态静态计量学参数改变。结果染氟组大鼠100%发生氟斑牙;染氟组大鼠骨氟含量[(199.90±106.84)mg/kg]与骨密度(0.205 3 g/cm2)明显高于对照组[分别为(30.06±6.11)mg/kg、0.185 4 g/cm2],差异有统计学意义(P<0.05);形态计量学结果显示,染氟组大鼠胫骨上端骨小梁面积[(67 612.02±1 662.23)mm2]、骨小梁周长[(7 655.44±918.05)mm]、骨小梁个数[(38.25±4.99)个/mm]均明显高于对照组[分别为(50 951.43±9 046.88)mm2、(5 172.42±789.70)mm、(27.75±4.19)个/mm](均P<0.05)。结论单纯低蛋白低钙条件下,过量氟暴露可导致大鼠骨形态计量学出现以骨软化为主的病理改变。

Objective To explore morphological changes of bone in the progress of coal-burning fluorosis in rats. Methods Rat coal burning fluorosis model was established under low-protein and low calcium;the contents of 24-hour urinary fluoride, bone fluoride, dental fluorosis were determined to judge the degree of the injury; bone mineral density of femur and tibia was determined using X-ray absorptiometry;morphological changes of femur cancellous bone ultrastruc- ture was observed with scanning electron microscope and morphogenetic changes of the tibia bone were detected with static measurement parameters. Results All rats in fluoride groups had dental fluorosis. Bone fluoride content（ 199. 90±106. 84 mg/kg） and bone mineral density（0. 205 3 g/cm2） of fluoride groups were significantly higher than those of control group（30. 06±6. 11 mg/kg and 0. 185 4 g/cm2 ）, with statistically significant differences （ P 〈 0. 05 for all ）. Morphometry showed that trabecular area of upper tibia of the rats in fluoride groups（67 612. 02±1 662. 23 mm2 ） ,tra- becular bone perimeter（ 7 655.44± 918.05 ram）, and the number of trabecular bone （38.25 ±4.99/ram） were signifi- cantly higher than those of the rats in control group （50 951.43 ± 9 046. 88 mm2,5 172.42 ± 789. 70 mm, and 27.75 ± 4. 19/mm;P 〈0. 05 for all）. Conclusion Under low-protein and low calcium condition, excessive fluoride exposure can lead to pathological changes of bone ,especially the changes of osteomalaeia in rats based on histomorphometric study.