甲状旁腺激素对去卵巢大鼠骨折愈合的影响

目的探讨局部应用甲状旁腺激素（PTH）对去卵巢大鼠股骨骨折愈合的影响。方法将30只SD大鼠随机分成3组：假手术组＋骨折＋生理盐水组（Sham＋F＋NS）;卵巢切除＋骨折＋生理盐水组（OVX＋F＋NS）;卵巢切除＋骨折＋甲状旁腺激素组（OVX＋F＋PTH）,每组10只。实验组切除双侧卵巢,术后4周选取股骨中段制备开放性骨折模型,髓内钉固定,于骨折部位给予PTH（20μg/kg）,3次/周,间断骨折局部皮下注射4周后,处死动物并收集样本,采用X线摄片、骨密度检测、组织形态学及免疫组织化学方法评估骨折愈合情况。结果给予PTH干预后,骨痂骨量较OVX＋F＋NS明组显升高（P〈0.05）;X线观察显示OVX＋F＋PTH组得分明显高于OVX＋F＋NS组（P〈0.05）;HE染色可见OVX＋F＋PTH组骨小梁数量增多,板层骨排列整齐有序;同时,OVX＋F＋PTH组骨形态发生蛋白-2（BMP-2）免疫组化表达明显升高（P〈0.05）。结论 PTH能够刺激成骨细胞活性,有效改善骨质疏松性骨折大鼠骨痂愈合质量。

Effect of parathyroid hormone on fraction healing in ovariectomized rats

Objective To investigate the role of PTH in the process of ovariectomized（OVX） rat femur fraction healing.Methods Thirty SD rats were randomly divided into three groups： the sham operation group ＋ fracture ＋ saline group（Sham＋F＋NS）;ovariectomy ＋ fracture ＋ saline group（OVX＋F＋NS）;ovariectomy ＋ fracture ＋ parathyroid hormone group（OVX＋F＋PTH）（n=10）.Both ovaries were cut in the experimental group.And four weeks later,fracture of the right middle femur was carried out in all the groups,and internal fixation was finished with kirschner wires.The rats were locally intermittently administrated with PTH（20 μg/kg） 3 times per week,and this treatment was done for 4 weeks,other rats were administrated with normal saline as the controls.The femurs were harvested after 4 weeks of fracture operation,then the callus were analyzed by X-ray and bone mineral density（BMD） examination,HE staining and immunochemistry staining.Results Compared to the vehicle group,BMD of callus was obviously increased by PTH treatment（P0.05）;By X-ray analysis,fracture healing in the OVX＋F＋PTH group was markedly superior to that in the OVX＋F＋NS group（P0.05）;morphologic observation showed that the number of trabeculae was increased,and the array of lamellar bone was in order in the OVX＋F＋PTH group.In the meantime,immunochemistry staining displayed that the expression of BMP-2 in the OVX＋F＋PTH group,was significantly stronger than that in the OVX＋F＋NS group（P0.05）.Conclusion PTH is able to contribute to speeding up fracture healing and improving callus quality by stimulating osteoblastic activity in OVX rats.