OBJECTIVE Low back pain is one of the most inextricable problems encountered in clinics. Animal models that imitate symptoms in humans are valuable tools for investigating low back pain mechanisms and the possible therapeutic applications. With the development of genetic technology in pain field, the possibility of mutating specific genes in mice has provided a potent tool for investigating the specific mechanisms of pain. The aim of the present study was to develop a mouse model of chronic compression of dorsal root ganglion (CCD), in which gene mutation can be applied to facilitate the studies of chronic pain. METHODS Chronic compression of L4 and L5 dorsal root ganglia was conducted in mice by inserting fine stainless steel rods into the intervertebral foramina, one at L4 and the other at L5. Mechanical allodynia and thermal hyperalgesia were examined with von Frey filaments and radiating heat stimulator, respectively. RESULTS The CCD mice displayed dramatic mechanical and thermal hyperalgesia as well as tactile allodynia in the hindpaw ipsilateral to CCD. In addition, this mechanical and thermal hyperalgesia as well as tactile allodynia was also found to spread to the contralateral hindpaw. CONCLUSION This model, combined with the possible genetic modification, will strengthen our knowledge of the underlying mechanisms of low back pain. It also favors the development of new treatment strategies for pain and hyperalgesia after spinal injury and other disorders which affect the dorsal root ganglion in humans.
目的: 腰背痛是一个临床常见的棘手问题。 动物模型可以很好地模拟人类的临床症状, 并为研究腰背痛的机制及其药物治疗带来希望。 随着转基因技术的发展, 特定的转基因小鼠模型为研究疼痛机制提供了一个强有力的工具。 本研究旨在建立慢性背根节压迫小鼠模型, 为应用转基因动物深入研究慢性痛的发生机制提供重要工具。
方法: 向小鼠腰4和腰5椎间孔内插入细钢柱造成腰4和腰5背根节慢性压迫模型, 采用von Frey细丝和辐射热刺激仪检测机械性痛敏和热痛敏。
结果: 小鼠一侧腰4和腰5背根节持续压迫后导致同侧肢体出现显著的机械性痛敏和热痛敏。 另外, 压迫的对侧肢体也出现了明显的机械性痛敏和热痛敏。
结论: 此模型的建立可以使转基因动物发挥优势, 并为治疗人类脊髓损伤和背根节异常后的疼痛和痛觉过敏提供新的对策。