Purpose/aim: Neuropathic pain following spinal cord injury (SCI) has a tremendous impact on patient's quality of life, and frequently is the most limiting aspect of the disease. In view of the severity of this condition and the absence of effective treatments, the establishment of a reliable animal model that reproduces neuropathic pain after injury is crucial for a better understanding of the pathophysiology and for the development of new therapeutic strategies. Thus, the objective of the present study was to standardize the traumatic SCI model in relation to neuropathic pain. MATERIALS AND METHODS Wistar rats were submitted to SCI of mild intensity (pendulum height 12.5 mm) or moderate intensity (pendulum height 25 mm) using the New York University Impactor equipment. Behavioural assessment was performed during 8 weeks. Thereafter, spinal cords were processed for immunohistochemistry. RESULTS The animals of the moderate injury group in comparison with mild injury had a greater motor function deficit, worse mechanical allodynia, and latter bladder recovery; moreover, histological analysis revealed more extensive lesions with lower neuronal population. CONCLUSIONS Our study suggests that moderate SCI causes a progressive and long-lasting painful condition (at least 8 weeks), in addition to motor impairment, and thus represents a reliable animal model for the study of chronic neuropathic pain after SCI.

中文翻译：

---

与大鼠神经性疼痛相关的创伤性脊髓损伤模型的特征。

目的/目的：脊髓损伤（SCI）后的神经性疼痛对患者的生活质量产生巨大影响，并且经常是该疾病的最大局限性方面。鉴于这种情况的严重性和缺乏有效的治疗方法，建立一个可靠的动物模型可以在受伤后重现神经性疼痛，对于更好地了解病理生理学和开发新的治疗策略至关重要。因此，本研究的目的是标准化与神经性疼痛有关的创伤性SCI模型。材料与方法使用纽约大学Impactor设备，将Wistar大鼠置于强度适中（摆高12.5 mm）或中等强度（摆高25 mm）的SCI。在8周内进行行为评估。之后，对脊髓进行免疫组织化学处理。结果与轻度损伤相比，中度损伤组的动物具有更大的运动功能障碍，较差的机械性异常性疼痛和较晚的膀胱恢复。此外，组织学分析显示，神经元数量较少，病变范围更大。结论我们的研究表明，中度SCI不仅会导致运动障碍，还会引起进行性和长期的疼痛状况（至少8周），因此代表了研究SCI后慢性神经性疼痛的可靠动物模型。组织学分析显示病变范围更广，神经元数量较少。结论我们的研究表明，中度SCI不仅会导致运动障碍，还会引起进行性和长期的疼痛状况（至少8周），因此代表了研究SCI后慢性神经性疼痛的可靠动物模型。组织学分析显示病变范围更广，神经元数量较少。结论我们的研究表明，中度SCI不仅会导致运动障碍，还会引起进行性和持久性疼痛（至少8周），因此代表了研究SCI后慢性神经性疼痛的可靠动物模型。