早期应用阿仑膦酸钠对脊髓损伤大鼠骨密度及生物力学特性的影响

Effect of early administration of alendronate on bone mineral density and biomechanical properties of the femur of spinal cord injuried rats.

目的探讨早期应用阿仑膦酸钠(ALN)对脊髓损伤(SCI)大鼠股骨骨密度及生物力学特性的影响。方法将36只3月龄雌性SD大鼠随机分为假手术组(Sham组)、SCI组、SCI+ALN组,假手术组仅行T10椎板切除,其余组行T10椎板切除、脊髓横断术。SCI+ALN组于术后1周开始腹腔注射ALN,每周3次。术后8周取股骨,进行骨密度及生物力学检测。结果脊髓横断术后8周大鼠股骨骨密度及生物力学参数与Sham组相比发生了显著性改变;与SCI组相比,SCI+ALN组股骨骨密度值显著升高(P<001);弹性载荷值、最大载荷值显著升高(P<001),最大应力值升高(P<005)。结论脊髓横断术后8周的大鼠可用于SCI后骨质疏松的研究;早期应用ALN可减少SCI大鼠股骨的骨量丢失,改善SCI大鼠股骨的生物力学特性。

ObjectiveTo observe the effect of early administration of alendronate on bone mineral density and biomechanical properties of the femur of spinal cord injuried rats.Methods36 3-month-old female SD rats were randomly divided into the Sham group, SCI group and SCI+ALN group. Rats in the Sham group underwent a sham procedure. Rats in the SCI group and in SCI+ALN group underwent spinal cord transection at the level of the tenth thoracic vertebra. Rats in the SCI+ALN group were injected with alendronate intraperitoneally 1 week after SCI, three times a week. All rats were sacrificed 8 week after operation. Bone mineral density and biomechanical properties of the femur were measured, respectively.ResultsBone mineral density and biomechanical properties of the femur changed significantly after spinal cord transection. After the treatment of alendronate injection, bone mineral density of the femur in the SCI+ALN group was significantly increased compared with that of the SCI group(P<0.01). Elastic loading and maximal loading of the femur in the SCI+ALN group was significantly increased compared with that of the SCI group(P<0.01). Maximal stress was significantly increased compared with that of the SCI group(P<0.05). ConclusionThe rats 8 week after spinal cord transection can be used in osteoporotic research following SCI. Early administration of ALN after SCI can inhibit bone resorption, improve biomechanical properties of the femur of spinal cord injured rats so as to prevent the development of osteoporosis and osteoporotic fracture. [