目的 :建立大鼠颈脊髓半侧挫伤模型,评价不同程度脊髓损伤大鼠的行为学和组织学改变。方法 :选取32只成年雄性Sprague-Dawley大鼠,体重为280~320g。按挫伤深度分为1.2mm组(n=12)和2mm组(n=12),并设立假手术组(n=8)对照。麻醉状态下后路手术暴露大鼠C5左侧脊髓,特制椎夹固定颈椎并连于大鼠立体定位架后置于脊髓打击器平台上,然后应用直径为1.5mm的圆柱形打击头在500mm/s的速度下分别以1.2mm和2mm打击深度背侧垂直挫伤大鼠C5脊髓左半侧,监测最大打击力和挫伤能量。每只大鼠损伤后进行前肢运动功能评分,圆柱攀爬试验和梳理试验。伤后8周取材,在脊髓横断面组织学切片上测量损伤中心处脊髓损伤面积,以及灰、白质残存面积。结果:中度损伤组最大打击力和挫伤能量分别为0.99±0.14N和(1.08±0.01)×10-5J,重度损伤组为1.53±0.22N和(8.56±0.02)×10-5J,两组间打击力和损伤能量具有统计学差异(P<0.05)。术后对照组大鼠均未见明显神经功能障碍,前肢运动功能评分为16.29±0.49。损伤组大鼠均出现单侧神经功能障碍,损伤同侧前肢运动功能评分中度损伤组为1.40±0.52,重度损伤组为0.83±0.25,两组无统计学差异(P>0.05)。伤后8周前肢运动功能评分中度损伤组为12.40±1.15,重度损伤组为8.41±0.83,对照组为17.00±0.00,梳理试验评分中度损伤组为3.80±0.60,重度损伤组为2.51±0.54,对照组为5.00±0.00,损伤同侧前肢使用比例中度损伤组为(32.31±5.70)%,重度损伤组为(4.92±1.21)%,对照组为(49.42±1.20)%,各组间均有统计学差异(P<0.05)。镜下观察损伤组大鼠脊髓组织都出现了明显的半侧空洞和结构破坏,而对侧脊髓结构基本完整。在损伤中心处,中度损伤组脊髓背侧束、背外侧束和脊髓后角有破坏,重度损伤组脊髓仅残留部分的腹外侧束,对照组脊髓组织结构完整。灰质和白质残存面积在中度损伤组分别为1.45±0.11mm~2和4.13±0.29mm~2,重度损伤组分别为1.10±0.05mm~2和3.84±0.19mm~2,组间均存在统计学差异(P<0.05)。结论:本研究成功建立了不同程度的大鼠颈脊髓半侧挫伤模型,不同挫伤深度表现出不同程度的单侧前肢运动功能障碍和脊髓组织破坏,为颈脊髓半侧损伤模型提供研究基础。 OBJECTIVE: To establish a rat model of hemisecondis contusion of the cervical spinal cord and evaluate the changes of behavior and histology in rats with different degrees of spinal cord injury. Methods: Thirty-two adult male Sprague-Dawley rats weighing 280-320g were selected. The depth of contusion was divided into 1.2mm group (n = 12) and 2mm group (n = 12), and the sham operation group (n = 8) control. Under anesthesia posterior surgery exposed left C5 rat spinal cord, a special vertebral clip fixed cervical spine and even connected to the rat stereotactic placed on the spinal cord percussion platform, and then use a diameter of 1.5mm cylindrical striking head in the 500mm / s at a speed of 1.2mm and 2mm respectively, the depth of the dorsal vertical contusion of the left side of the C5 spinal cord of rats to monitor the maximum impact force and contusion energy. Forearm motor function scores, cylindrical climbing tests and carding tests were performed on each rat after injury. Eight weeks after injury, the area of ​​spinal cord injury and the area of ​​residual gray and white matter were measured on the transverse section of the spinal cord. RESULTS: The maximal striking power and contusion energy of moderate injury group were 0.99 ± 0.14N and (1.08 ± 0.01) × 10-5J, respectively. The severe injury group was 1.53 ± 0.22N and (8.56 ± 0.02) × 10-5J, There was a significant difference between striking power and damage energy (P <0.05). No significant neurological dysfunction was found in the control rats, and the motor function score of forelimb was 16.29 ± 0.49. Unilateral nerve dysfunction occurred in rats in injury group. The mean motor function impairment in injured ipsilateral forearm was 1.40 ± 0.52 in severe injury group, and 0.83 ± 0.25 in severe injury group. There was no significant difference between the two groups (P> 0.05). At 8 weeks after injury, the scores of forelimb motor function in moderate injury group were 12.40 ± 1.15, those in severe injury group were 8.41 ± 0.83, those in control group were 17.00 ± 0.00, those in moderate injury group were 3.80 ± 0.60 and those in severe injury group were 2.51 ± 0.54 in the control group and 5.00 ± 0.00 in the control group, and the proportion of the injured ipsilateral forelimb was (32.31 ± 5.70)% in the moderate injury group, (4.92 ± 1.21)% in the severe injury group and (49.42 ± 1.20)% in the control group Between the two groups were statistically significant (P <0.05). Microscopically, the injured spinal cord tissue of the injured group showed obviously half-cavity and structural damage, while contralateral spinal cord structure was basically intact. At the lesion center, the spinal dorsal, dorsolateral and spinal dorsal horn of the moderate injury group were damaged. Only the residual part of the ventral lateral bundle of the spinal cord of the severe injury group was intact. The spinal cord tissue of the control group was intact. The residual area of ​​gray matter and white matter were 1.45 ± 0.11mm ~ 2 and 4.13 ± 0.29mm ~ 2 in moderate injury group, and 1.10 ± 0.05mm ~ 2 and 3.84 ± 0.19mm ~ 2 in severe injury group respectively Learning difference (P <0.05). CONCLUSIONS: In this study, different degrees of cervical half-contusion model of cervical spinal cord were successfully established in rats. Different contusion depths showed different degrees of unilateral motor dysfunction and spinal cord tissue destruction, which provided the basis for the study of hemizygous and spinal cord injury models.