双足直立诱导低褪黑素水平雌性小鼠脊柱侧凸模型的观察

The effect of bipedal amputation on a scoliosis model of female mouse with low melatonin level

目的：观察双足直立诱导低褪黑素水平雌性C57BL/6j小鼠脊柱侧凸的发生情况，为选择理想的特发性脊柱侧凸模型提供依据。方法：选取低褪黑素水平C57BL/6j小鼠雌、雄各20只，分为低褪黑素雌性小鼠组（A组）、低褪黑素雄性小鼠组（B组），另选C3He/ej雄性小鼠20只作为对照组（C组）。将三组小鼠均于３周龄时施行双上肢截肢合并鼠尾切除术建立双足直立小鼠模型，然后进行直立体态诱导。术后4个月，采用X线片评估三组小鼠脊柱侧凸发生情况，比较三组间脊柱侧凸发生率和侧凸严重程度。结果：三组小鼠建模后经直立体态诱导均可长时间保持直立体态。A组19只发生脊柱侧凸，侧凸小鼠Cobb角17°~36°，平均24.6°±6.0°；B组16只发生脊柱侧凸，侧凸小鼠Cobb角13°~31°，平均20.8°±4.3°；C组9只发生脊柱侧凸，侧凸小鼠Cobb角13°~23°，平均18.3°±2.7°。A、B组小鼠脊柱侧凸发生率均明显高于C组（χ2=11.904，P=0.005；χ2=5.2267，P=0.023），A、B两组脊柱侧凸发生率无显著性差异（P〈0.05）。A组脊柱侧凸Cobb角明显高于B组（t=2.096，P=0.044）和C组（t=3.646，P=0.001）；B组与C组Cobb角无显著性差异（P〉0.05）。结论：雌性低褪黑素双足直立小鼠脊柱侧凸发生率高，脊柱侧凸更严重，可以较好模拟特发性脊柱侧凸的发生发展过程，为特发性脊柱侧凸相关研究提供良好平台。

Objectives： To establish a better adolescent idiopathic scoliosis（AIS） model of bipedal amputated mouse with low melatonin level. Methods： Twenty C57BL/6j female mice and twenty male mice were chosen to serve as low melatonin and divided into two groups according to gender, and twenty C3He/ej male mice were treated as controls. Amputation of forelimbs and tail was performed at 3 weeks old in three groups. After amputation, all these bipedal amputated mice were trained to keep a standing posture. Then X-rays were obtained at the 4th month to determine the development of spinal deformity. Comparisons on the incidence of scoliosis, and curve magnitude were performed among groups. Results： After establishing models, all mice were capable of keeping a standing posture for a long time. Scoliosis was observed in 19 out of 20 C57BL/6j female mice with an average Cobb angle of 24.6°±6.0°（range, 17° to 36°）, in 16 out of 20 C57BL/6j male mice with an average Cobb angle of 20.8°±4.3°（range, 13° to 31°） and in 9 out of 20 controls with an average Cobb angle of 18.3°±2.7°（range, 13° to 23°）. Conclusions： A higher scoliosis incidence and more severe curve are observed in C57BL/6j female bipedal mice compared with C57BL/6j male bipedal mice and control mice, which indicates that this model can be used for the research of AIS.