Expression of endomcrphine along pain puthuay in experimental peripmend neuropathy in rat

周围神经损伤后，患者有时会出现顽固性疼痛，如疱疹后神经痛、cause痛等，非甾体类抗炎药或阿片类药物对此类情况无效。我们利用大鼠坐骨神经损伤模型，发现电惊厥治疗和鞘内给药锂对神经损伤后疼痛有效。这些研究表明，中枢神经系统相关的情感成分可能是治疗神经性疼痛的主要目标。在本研究的第一阶段，我们计划利用免疫细胞化学技术研究疼痛传递道中内啡肽和痛觉肽的变化，因为我们推测阿片类药物对神经性疼痛的不良效果可能是由于这些阿片类系统的改变。但内啡肽和痛觉啡的抗体效果不佳，因此我们改变了本研究的方案。本研究探讨了锂对肌肌醇联合给药神经损伤后疼痛缓解作用的机制。鞘内联合肌醇可逆转锂对神经损伤后疼痛的影响，提示第二信使系统在锂对神经损伤后疼痛的影响中起重要作用。我们还研究了氟烷麻醉下反复刺激损伤神经是否能减轻神经损伤后的疼痛。我们还发现氟烷麻醉下反复刺激损伤神经可以减轻神经损伤后的疼痛，提示长期抑郁可能有助于神经损伤后疼痛的缓解。这些结果鼓励了神经性疼痛的新治疗方法。

After peripheral nerve injury, patients sometimes suffer from refractory pain, such as post herpetic neuralgia and causalgia Non-steroidal anti-inflammatory drugs or opioid are not effective for such condition. We, using sciatic nerve injury model in rat, showed that electro-convulsive treatment and intrathecal administration of lithium are effective for pain after nerve injury. These studies suggest that central nervotus system relating affective component can be a primary target for treating neuropathic pain.At first stage in this study, we planned to investigate about change of endomorphine and nociceptinalong pain transmitting tract by using immuno-cytochemistry technique because we speculated that poor effect of opioid for neuropathic pain might be due to changes in these opioid system. However antibody for endomorphine and nociceptin did not work well, so, we changed the protocol of this study. In this study we investigated about mechanism of lithium on pain relieving effect after nerve injury by co-administrating myo-inositol. Intrathecal co-administration of myo-inositol reversed the effect of lithitum on pain after nerve injury, which suggests that second messenger system had important role for lithium effect on pain after nerve injury. We also examined whether repetitive stimulation to injured nerve under halothane anesthesia could relieve pain after nerve injury. We also showed that repetitive stimulation to injured nerve under halothane anesthesia could relieve pain after nerve injury, suggesting long term depression may contribute for pain relief after nerve injury. These results encourage the new therapetttic approach for neuropathic pain.