Therapy for intractable pain by intrathecal administration of antisense oligonucleotides of neurotrophic factor

1.观察大鼠足底切口后脊髓背角c-Fos蛋白（Fos）表达的时空变化及局麻药预处理的影响。我们的研究结果表明，虽然局部麻醉剂预处理抑制术后Fos表达数天，但仅在局部麻醉剂使用的预期持续时间内观察到镇痛效果。2.我们检测了脊髓中环氧化酶（考克斯）-2和trkB受体的mRNA，以及在患有L5脊神经结扎（SNL）诱导的神经病的大鼠的后爪中注射福尔马林之后背根神经节（DRG）中的脑源性神经营养因子（BDNF）。我们还测量了脊髓中c-fos mRNA的表达，以阐明中枢通路中神经元活动的变化。c-fos研究提示SNL诱发神经病变后脊髓对炎症痛反应的神经元活动减少可能在急性痛感觉改变中起重要作用。SNL诱导的神经病变后BDNF mRNA表达增加，提示BDNF在脊髓中的过表达可以减轻福尔马林诱导的疼痛。3.建立了脊髓水平BDNF mRNA的定量方法。因此，我们能够量化非常少量的神经营养因子。同时，我们还建立了原位杂交和鞘内给药技术。神经营养因子的反义RNA可以在神经病理性疼痛模型中鞘内施用。

1.We investigated the spatial and temporal patterns of c-Fos protein (Fos) expression in the dorsal horn of the spinal cord caused by plantar incision in the rat and the effects of pretreatment with local anesthetics. Our results indicate that although pretreatment with local anesthetics suppresses Fos expression for several days in the postoperative period, the analgesic effect is observed only for the expected duration of the local anesthetic used.2.We measured the mRNAs of cyclooxygenase(COX)-2, and trkB receptor in the spinal cord, and also brain-derived neurotrophic factor(BDNF) in the dorsal root ganglion(DRG) after an injection of formalin in the hind paw of a rat with L5 spinal nerve ligation(SNL)-induced neuropathy. We also measured c-fos mRNA expression in the spinal cord to clarify changes in neuronal activities in the central pathways. c-fos study indicates that the decrease in neuronal activities to inflammation pain in the spinal cord after SNL-induced neuropathy may play an important role in changing in the perception of acute pain. Increase in mRNA of BDNF after SNL-induced neuropathy suggests that overexpression of BDNF in the spinal cord could alleviate formalin-induced pain.3.We established the real-time PCR method to quantify mRNA in the spinal level. Consequently, we became able to quantify a very small amount of neurotrophic factors. Furthermore, we got a technique of in situ hybridization and intrathecal administration of drugs. Antisense RNA of neurotrophic factors can be administered intrathecally in the neuropathic pain model.