用电解损毁方法制备大鼠的脊髓损伤模型

目的：建立一种简便实用、稳定可靠的脊髓损伤动物模型。方法：采用电解损毁法，主要损伤大鼠第１０胸椎节段脊髓双侧皮质脊髓束纤维，在术后不同时间观察受损脊髓组织学变化及大鼠运动功能改变，并用ＨＲＰ逆行标记技术，以大脑运动皮层标记神经元计数来反映皮质脊髓束受损情况。结果：１ｍＡ，２１０ｓ的损伤电流，可在脊髓后索造成神经组织坏死，形成空腔，使双侧皮质脊髓束纤维受损；术后１周、２周、３周观察，电损毁组大鼠运动功能显著低于假手术组，表现为后肢运动评分下降，Ａｓｈｗｏｒｔｈ肌张力评分增大，斜板实验角度下降；电损毁组运动皮质标记神经元计数也显著低于假手术组。结论：电解损毁在适宜参数下能损伤双侧脊髓皮质脊髓束，引起双后肢的不完全性截瘫，结果稳定可靠，操作简便，为脊髓损伤的实验研究奠定了基础。

The electrolytic lesion as a model of spinal cord injury in adult rat

Objective: To set up a practical and reliable animal model of spinal cord injury. Methods: Electrolytic lesion was made on bilateral corticospinal tract (CST) in rat at the 10th thoracic vertebra level. At different time of post injury, the histological change of lesioned spinal cord, the behavioral manifestation and the HRP labeled neuron counts in the motor cortex which reflect the damage of CST was evaluated. Results: Current of 1 mA, 210 s could cause necrosis and cavitation in the dorsal funiculus, resulting in bilateral corticospinal tract injury; rats with electrolytic lesions exhibited declined motor function with decreased Tarlov score, increased Ashworth score and reduced inclined plane angle, the HRP labeled neuron counts in motor cortex were also significantly lower in the lesioned group than sham operation group. Conclusion: Electrolytic lesion of the bilateral corticospinal tract could cause incomplete paraplegia in the hind limbs. The study has proorded a base for research on spinal cord injury with dependable results.