燃煤型氟中毒大鼠血清中Ⅰ型胶原交联N末端肽变化

Serum N-telopeptide of Type Ⅰ Collagen in Rats with Coal-Burning Type Fluorosis

目的观察血清Ⅰ型胶原交联N末端肽(NTX)在燃煤型氟中毒大鼠血清中的变化,探讨骨吸收在氟骨症发生中的地位。方法将160只断乳4周的SD大鼠随机分为对照组、低氟组、中氟组、高氟组,食用病区煤烘玉米,复制燃煤型氟中毒动物模型。分别于染毒后30 d、90 d、180 d分批处死动物,ELISA法检测血清NTX水平。结果随着染毒时间增加,各实验组尿氟、骨氟、氟斑牙发生率、股骨病理积分逐渐增加(P小于0.05)。实验不同阶段各实验组与对照组比较,差异具有统计学意义(P小于0.05),并有随着染氟剂量增加而增加的趋势(P小于0.05)。实验30 d和90 d时,各组NTX水平差异无统计学意义。实验180 d时,低氟组及中氟组NTX高于对照组及高氟组(P小于0.05)。结论在摄氟早期,氟未增强骨吸收,随着时间及染氟剂量增加,可促进骨吸收。

Objectives To observe the change of serum N-telopeptide of type I collagen （NTX） in rats with coal-burning type fluorosis, and to explore the role of bone resorption in skeletal fluorosis. Methods One hundred and sixty SD rats at 4 weeks after weaning were divided into four groups, including a control group and three fuoride groups. The rats in fluoride groups were fed with corn （at low- medium- and high-dose level） roasted with coal from a fluorosis endemic area. The rats were executed at the 30^th, 90^th and 180^th day of the experiment respectively. The level of NTX in serum was tested by ELISA. Results The concentration of fluoride in urine and bone, the incidence of dental fluorosis, and the pathological score of thighbone were higher with longer-term of fluorosis （P less than 0.05）. There were no statistic difference for NTX among the four groups at the 30^th and 90^th day of the experiment; but the NTX levels of low-dose group and medium-dose group were higher than that of high dose and control group at the 180^th day of the experiment. Conclusions At the beginning of taking high fluoride diet, the bone resorption was not strengthened. With the increase of dosage and duration of taking fluoride, the bone resorption was promoted.