Peripheral nerve injury activates convergent nociceptive input to dorsal horn neurons from neighboring intact nerve
Peripheral nerve injury activates convergent nociceptive input to dorsal horn neurons from neighboring intact nerve
复制标题
周围神经损伤激活邻近完整神经对背角神经元的汇聚伤害性输入
DOI：
10.1007/s00221-015-4203-2
复制
发表时间：
2015
期刊：
影响因子：
2
通讯作者：
Sugimoto T
中科院分区：
文献类型：
--
作者：
Terayama R;Yamamoto Y;Kishimoto N;Maruhama K;Mizutani M;Iida S;Sugimoto T
以往的研究表明，周围神经损伤引起脊髓背角神经元过度的伤害性反应，这种变化被认为反映了神经病理性疼痛状态的发展。本研究的目的是检查脊髓背角的会聚的伤害性输入的二级神经元的传入周围神经损伤。应用免疫荧光双标记技术检测隐神经损伤后脊髓背角神经元的会聚性突触传入，观察c-Fos和磷酸化细胞外信号调节激酶（p-ERK）的表达。伤害性热刺激后爪和电刺激损伤或未损伤隐神经分别诱导c-Fos表达和ERK磷酸化。在隐神经的中央终末领域内，c-Fos蛋白样免疫反应（c-Fos-IR）细胞的数量在损伤后3天显著减少，并在14天恢复到对照水平。隐神经损伤后，p-ERK免疫反应阳性细胞分布于隐神经中央终末野，其分布形态和数量无明显变化。损伤后双标记细胞谱的变化与c-Fos-IR细胞谱的变化相似。这些结果表明，通过邻近完整神经的会聚性初级伤害性输入有助于脊髓背角伤害性神经元的反应性增加。
Previous studies demonstrated that peripheral nerve injury induced excessive nociceptive response of spinal cord dorsal horn neurons and such change has been proposed to reflect the development of neuropathic pain state. The aim of this study was to examine the spinal dorsal horn for convergence of nociceptive input to second-order neurons deafferented by peripheral nerve injury. Double immunofluorescence labeling for c-Fos and phosphorylated extracellular signal-regulated kinase (p-ERK) was performed to detect convergent synaptic input to spinal dorsal horn neurons after the saphenous nerve injury. c-Fos expression and the phosphorylation of ERK were induced by noxious heat stimulation of the hindpaw and by electrical stimulation of the injured or uninjured saphenous nerve, respectively. Within the central terminal field of the saphenous nerve, the number of c-Fos protein-like immunoreactive (c-Fos-IR) cell profiles was significantly decreased at 3 days and returned to the control level by 14 days after the injury. p-ERK immunoreactive (p-ERK-IR) cell profiles were distributed in the central terminal field of the saphenous nerve, and the topographic distribution pattern and number of such p-ERK-IR cell profiles remained unchanged after the nerve injury. The time course of changes in the number of double-labeled cell profiles was similar to that of c-Fos-IR cell profiles after the injury. These results indicate that convergent primary nociceptive input through neighboring intact nerves contributes to increased responsiveness of spinal dorsal horn nociceptive neurons.