构建脊髓慢性压迫损伤模型大鼠巢蛋白的表达规律

Nestin expression in a rat model of chronic compressive spinal cord lesion

背景:既往应用的脊髓损伤动物模型难以达到一种慢性渐进性的压迫效果,与人体慢性脊髓压迫损伤机制有很大的不同。目的:构建一种新的脊髓慢性压迫性损伤模型大鼠,探究慢性压迫损伤后脊髓损伤区域巢蛋白的表达规律及其意义。方法:Wistar大鼠40只随机分为实验组30只和对照组10只。实验组大鼠取下胸7、8椎板,植入压迫材料,形成慢性压迫脊髓损伤模型。植入后第1,3,7,14,28天,取压迫处脊髓组织,行病理学检查及巢蛋白免疫组织化学染色,半定量反转录PCR反应测定巢蛋白mRNA的表达,同时测量压迫段椎管直径及缓膨胀材料侵占厚度。结果与结论:随压迫时间的延长,实验组大鼠椎管侵占率逐渐增加,脊髓组织出现坏死等情况,大鼠BBB评分降低,压迫处脊髓组织中Nestin mRNA及蛋白表达至伤后7d时达到高峰,而后表达逐渐下降,说明实验成功建立慢性脊髓压迫损伤动物模型,且慢性脊髓压迫损伤大鼠脊髓组织Nestin mRNA及蛋白呈动态变化。

BACKGROUND：Chronic progressive compressive spinal cord injury is difficult to reach in animal models, and the underlying mechanisms differ greatly from that in humans. OBJECTIVE：To construct a new rat model of chronic progressive compressive spinal cord injury and to investigate nestin expression rule and significance in spinal cord injury area after chronic progressive compressive spinal cord injury. METHODS：Forty rats were randomly divided into an experimental group （n = 30） and a control group （n = 10）. Rat 7, 8 vertebral plates were removed and were filled with water-swelling material to establish rat models of chronic progressive compressive spinal cord injury. At 1, 3, 7, 14, and 28 days after implantation, spinal cord tissue at the compressive region was harvested for pathological examination and nestin immunohistochemical staining. Nestin mRNA expression was determined by semi-quantitative reverse transcription PCR. The vertebral canal diameter at the compressive segment and the thickness of expansive material were simultaneously determined. RESULTS AND CONCLUSION：In the experimental group, with the prolonged time, vertebral canal occupied was gradually enlarged, necrotic spinal cord tissue was observed, rat BBB scores were decreased, nestin mRNA and protein expression in the compressive spinal cord tissue peaked 7 days after injury and then tended to decrease. These findings suggest that chronic compressive spinal cord injury was successfully induced in rats, and nestin mRNA and protein expression in such an animal model exhibit dynamic changes.