Regenerations of Spinal Neurons and its Sensory Function in Pathological Pain following Peripheral Nerve Injury

外周神经损伤后病理性疼痛中外周-脊髓感觉系统的神经元再生是近年来研究的热点。然而，关于骨髓基质细胞（BMSc）移植或营养因子治疗细胞和功能紊乱的再生尚无报道。我们使用成熟的大鼠模型研究了病理性疼痛脊髓神经元再生的可能性，已知谷氨酸和sP的过度释放启动胞内核加工的扰动，导致Ca2+增加。此外，我们还研究了骨髓间充质干细胞移植到脊髓和4甲基儿管酚胺（4- mc）合成神经生长因子的可能性。将大鼠分为BMSc组和4-MC组。在骨髓间充质干细胞的研究中，大鼠在骨髓间充质干细胞植入后，以完全性和触觉诱发的异常性疼痛联合星形胶质细胞生长的方式遭受脊髓损伤。在4-MC研究中，神经性疼痛是由左侧坐骨神经的压迫引起的。测定脊髓损伤后的疼痛反应（热痛觉过敏）、c-fos表达、细胞凋亡（TUNEL）和星形胶质细胞（GFAP）。治疗方法分别为(1)4-MC,(2)磁场刺激（MFS）， (3) n型钙离子进入阻断剂联合抗ngf。鞘内骨髓间充质干细胞移植后，四分之一的大鼠步态和疼痛感觉得到改善。在这些改良的动物中，在脊髓的腹角和背角都有明显的星形细胞生长。另一方面，坐骨神经损伤后，大鼠在5 ~ 10 d内出现热痛觉过敏，脊髓谷氨酸释放增加，且随时间延长而增强。痛觉过敏早期，脊髓表层有c- enemy蛋白表达和细胞凋亡，随后层压3-4（中间神经元）坏死。痛觉减少的动物在神经损伤后选择性损伤神经元的Rexed III周围出现星形胶质细胞生长。4-MC可显著改善神经性疼痛，并降低脊髓神经元c- enemy、凋亡、坏死和GFAP免疫反应性。4-MC给药，导致脑衍生营养因子和NGF的合成诱导，从而减弱脊髓谷氨酸释放和细胞内信号传导，包括c-foes，从而抑制这些组织病理变化。在此基础上，我们论证了骨髓间充质干细胞和营养因子对周围神经损伤后疼痛感觉的改善作用。在这些功能恢复中，神经细胞和星形胶质细胞在脊髓易损区Rexed III的再生作为解除抑制机制引起疼痛促进。另外，周围神经生长因子在磁场刺激下诱导脊髓神经元再生，与病理性疼痛等感觉系统的衰减有关。对于慢性疼痛的转变，提示了中间神经元的功能障碍，并促进了对神经免疫网络机制的进一步了解。这证明了骨髓基质细胞和营养因子治疗在临床上功能恢复中的应用。未来的研究方向是进一步确认骨髓基质细胞移植的安全性，为神经性疼痛的治疗提供可能。少

The neuronal regeneration of the peripheral-spinal cord sensory system in pathological pain after peripheral nerve injury has recently focused. However, there are no report concerning with either bone marrow stromal cell (BMSc) transplantation or trophic factor treatment for regeneration of cellular and functional derangements. We investigated the possibility of regeneration of spinal cord neurons of pathological pain using well-established rat model, which is known that the excessive release of glutamate and sP initiate perturbation of intracellular-nucleus processing resulting in increased Ca2+. In addition, we investigated possibilities for treatment by BMSc transplantation into spinal cord and synthesis of nerve growth factor by 4 methyl cathechol amine (4-MC).The rats were divided into following two studies, BMSc and 4-MC study, respectively. In BMSc study, rats were subjected to spinal cord injury by completion and touch-evoked allodynia combined with astrocyte growing after BMSc … More implantation (cultured neruspheas). In 4-MC study, the neuropathic pain was produced by legation of left sciatic nerve. The pain response (thermal hyperalgesia) combined with c-fos expression, apoptosis (TUNEL), and GFAP (astrocyte) at spinal cord were measured after nerve injury. For the treatment, (1) 4-MC, (2) magnetic field stimulation (MFS), (3) N-type Ca entry blocker, combined with anti-NGF, was respectively administered.After transplantation of intrathecal BMSc one fourth of rats can gait and pain sensation was improved. In these improved animals, astrocyte growing was evident at both ventral and dorsal horn of spinal cord. On the other hands, after sciatic nerve injury, rats showed thermal hyperalgesia accompanied with increased spinal glutamate release during 5-10 days and that was enhanced with time. There were c-foes protein expression and apoptosis of superficial layer of spinal cord during early state of the hyperalgesia followed by the necrosis of the laminate 3-4 (interneuron). In decreased pain sensation animals appeared astrocyte growing at around Rexed III where is selectively damaged neurons after nerve injury. 4-MC significantly improved neuropathic pain associated with decreased incidences of c-foes, apoptosis, necrosis, and GFAP immunoreactivity of spinal cord neurons. 4-MC administration, which brings about the synthesis induction of the Brain derivated trophic factor and NGF that it attenuates the spinal glutamate release, and intracellular signaling including c-foes and that, suppresses these histopathological changes.Based on present study, we demonstrated that possible improvement of pain sensation by peripheral nerve injury by injecting BMSc and trophic factor. In these functional recovery, the regeneration of neuron and astrocytes in Rexed III of spinal cord where is known as velnerable region and causes pain facilitation as disinhibitiom mechanisms. Otherwise, the peripheral nerve growth factors induced by magnetic field stimulation in regeneration of spinal cord neurons and related to attenuation of sensory systems such that of pathological pain. For the conversion to chronic pain, it was indicated that the dysfunction of the interneuron was concerned, and promotes further understand mechanisms of the nerve - immune network. It proves application of bone marrow stromal cells and trophic factor treatments to the functional recovery in the clinical situation As future direction, it will be needed to confirm safety of transplantation for possible treatment for neuropathic pain. Less