The effect of site and type of nerve injury on the expression of brain-derived neurotrophic factor in the dorsal root ganglion and on neuropathic pain behavior
The effect of site and type of nerve injury on the expression of brain-derived neurotrophic factor in the dorsal root ganglion and on neuropathic pain behavior
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DOI：
10.1016/j.neuroscience.2005.10.015
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发表时间：
2006-12
期刊：
影响因子：
3.3
通讯作者：
K. Obata;H. Yamanaka;Kimiko Kobayashi;Yi Dai;Toshiyuki Mizushima;Hirokazu Katsura;T. Fukuoka;A. To
中科院分区：
文献类型：
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作者：
K. Obata;H. Yamanaka;Kimiko Kobayashi;Yi Dai;Toshiyuki Mizushima;Hirokazu Katsura;T. Fukuoka;A. To
已经开发了许多大鼠神经病模型来模拟人类神经性疼痛状况，例如自发性疼痛、痛觉过敏和异常性疼痛。在本研究中，为了确定损伤部位（初级传入神经元的近端或远端）和损伤类型（运动或感觉）的相对重要性，我们检查了假手术大鼠背根神经节中的疼痛相关行为和脑源性神经营养因子表达的变化，以及L5背神经根切断术、L5腹神经根切断术、L5背神经根切断术中的脑源性神经营养因子表达的变化。 神经根切断术+腹侧神经根切断术和L5脊神经横断模型。 L5腹侧神经根切断术和脊神经横断不仅产生机械和热超敏反应，而且术后7天L5背根神经节中脑源性神经营养因子mRNA/蛋白增加。相比之下，尽管 L5 背根神经节中型和大型神经元的脑源性神经营养因子上调，但 L5 背根切断术组和背根切断术 + 腹根切断术组的大鼠在术后 7 天没有表现出这两种疼痛行为。另一方面，术后7天，L5脊神经横断，而不是背根切断术、背根切断术+腹根切断术或腹根切断术，增加了L4背根神经节中脑源性神经营养因子的表达。综上所述，这些发现表明，L4和L5背根神经节神经元中脑源性神经营养因子表达的上调可能至少部分参与神经病理性疼痛的病理生理机制，并且选择性神经根损伤模型可能有助于研究神经损伤后慢性疼痛的潜在机制。
A number of rat neuropathy models have been developed to simulate human neuropathic pain conditions, such as spontaneous pain, hyperalgesia, and allodynia. In the present study, to determine the relative importance of injury site (proximal or distal to the primary afferent neurons) and injury type (motor or sensory), we examined pain-related behaviors and changes of brain-derived neurotrophic factor expression in the dorsal root ganglion in sham-operated rats, and in the L5 dorsal rhizotomy, L5 ventral rhizotomy, L5 dorsal rhizotomy+ventral rhizotomy, and L5 spinal nerve transection models. L5 ventral rhizotomy and spinal nerve transection produced not only mechanical and heat hypersensitivity, but also an increase in brain-derived neurotrophic factor mRNA/protein in the L5 dorsal root ganglion at 7 days after surgery. In contrast, rats in the L5 dorsal rhizotomy and dorsal rhizotomy+ventral rhizotomy groups did not show both pain behaviors at 7 days after surgery, despite brain-derived neurotrophic factor upregulation in medium- and large-size neurons in the L5 dorsal root ganglion. On the other hand, L5 spinal nerve transection, but not dorsal rhizotomy, dorsal rhizotomy+ventral rhizotomy or ventral rhizotomy, increased the expression of brain-derived neurotrophic factor in the L4 dorsal root ganglion at 7 days after surgery. Taken together, these findings suggest that the upregulation of brain-derived neurotrophic factor expression in the L4 and L5 dorsal root ganglion neurons may be, at least in part, involved in the pathophysiological mechanisms of neuropathic pain and that the selective nerve root injury models may be useful for studying the underlying mechanisms of chronic pain after nerve injury.