一氧化氮调节骨折愈合的实验研究

Research of nitric oxide in modulating fracture healing

[目的]探讨一氧化氮在骨折愈合中的可能作用。[方法]Wistar大鼠60只随机分为实验组和对照组。两组动物的饮用水分别含L-硝基-精氨酸甲基脂(LNAME)和D-硝基-精氨酸甲基脂(DNAME),建立股骨开放骨折模型,骨折后第3d、1、2和4周,取每组6只大鼠骨折处骨痂行HE染色观察。另6只大鼠于骨折后4周行骨痂的面积、骨密度和骨折的生物力学评价。[结果]骨折后两组大鼠体重增加无差别。HE染色光镜下见骨折后不同时期L-NAME组骨折处骨痂生成少,骨痂塑形慢,未成熟细胞比例较对照组多(P<0.05),加入LNAME后使骨折愈合反应减小,实验组骨痂的大小、骨密度和愈合强度均明显低于对照组,有明显的统计学意义。[结论]在骨折愈合过程中加入LNAME会使骨折愈合减慢,一氧化氮可能促进骨折的愈合过程。

[ Objective] To evaluate the possible function of nitric oxide（ NO ） in fracture healing. L Method J Sixty wistar rats were divided into two groups randomly to study the effect of suppression of NO synthesis on fracture healing, rats in experimental group were fed with L-Nitroso-arginine methyl ester （L-NAME） , and in the control group were fed with its inactive enantiomer, D-Nitroso-arginine methyl ester（D-NAME）. The model of open fracture was built in the right femur of each rat. Callus from the fractured site was amputated and observed by the gross appearance and HE staining in the 3rd day, the first, second and fourth week after fracture. Another 6 callus specimens at the 4^th week were evaluated by theircross-sectional area, bone mineral density and healing intensity.[Result] The gross observation of fracture in different time points indicated relatively small callus after L-NAME intaking. A lower proportion of immature cells in the experimental group was observed compared with the control group with HE staining （ P 〈 0.05 ）. A 20% and 17% decrease （ P 〈 0.01 ） in cross-sectional area and bone mineral density was seen in experimental group respectively. The force breaking the healed femur also had a significant difference （ P 〈 0.05 ） in rats fed with L-NAME. [Conclusion] L-NAME＇s intake inhibits the healing intensity after fracture, which indicates NO plays an important role in the process of fracture healing.