Expansion of formalin-evoked Fos-immunoreactivity in rats with a spinal cord injury
Expansion of formalin-evoked Fos-immunoreactivity in rats with a spinal cord injury
复制标题
DOI：
10.1016/j.neures.2007.04.011
复制
发表时间：
2007-08-01
影响因子：
2.9
通讯作者：
Sagen, Jacqueline
中科院分区：
文献类型：
--
作者：
Castellanos, Daniel A.;Daniels, Linda A.;Sagen, Jacqueline
外周组织损伤和脊髓损伤（SCI）可能导致背角神经元的致敏和伤害性加工的改变。因此，SO患者所经历的外周损伤，即使最初未被察觉，也可能导致背角神经元持续和广泛的激活，并表现为慢性疼痛，并伴有干预修复或SCI适度恢复。为了观察大鼠完全SO后脊髓神经元对外周组织损伤的反应，我们定量测定了脊髓中的神经转录因子Fos。在T8水平脊髓完全横断或假手术（椎板切除术）两周后，在大鼠左后爪注射福尔马林。假手术大鼠在注射福尔马林后表现出双相后爪痛相关行为，而横切大鼠在第二（强直）期表现出较少的行为。假手术组的体视学分析显示，福尔马林诱导的Fos表达范围在腰椎背角内，在同侧背角和对侧有许多Fos样免疫反应谱。与假手术组相比，横切组fos样免疫反应性水平显著升高，范围扩大，在正常椎板分布区，以及多节段至骶骨水平均有所增加，对侧背角节段也有所增加。数据表明，尽管疼痛反应性降低，但受损脊髓外周损伤后脊髓，特别是背角神经元的广泛激活可能发生，并表明随着脊髓恢复或修复的进展，可能出现夸大的疼痛。(c) 2007爱思唯尔爱尔兰有限公司和日本神经科学学会。版权所有。
Peripheral tissue injury as well as spinal cord injury (SCI) may lead to sensitization of dorsal horn neurons and alterations in nociceptive processing. Thus, peripheral injuries experienced by SO patients, even if not initially perceived, could result in a persistent and widespread activation of dorsal horn neurons and emerge as chronic pain with interventive repair or modest recovery from SCI. To visualize the spinal neuron response to peripheral tissue injury following complete SO in rats, the neural transcription factor Fos was quantitated in the spinal cord. Two weeks following either a complete transection of the spinal cord at the level of T8 or a sham surgery (laminectomy), rats were injected with formalin into the left hind paw. Sham-operated rats demonstrated biphasic hind paw pain-related behavior following formalin injection, but transected rats displayed fewer behaviors in the second (tonic) phase. Stereological analysis of the sham group revealed that the extent of formalin-induced Fos expression was within the lumbar dorsal horn, with numerous Fos-like immunoreactive profiles in the ipsilateral dorsal horn and some contralateral immunoreactive profiles. In contrast, the level of Fos-like immunoreactivity in the transected group was significantly elevated and expanded in range compared to the sham group, with increases observed in the normal laminar distribution regions, as well as multi-segmentally through sacral levels and increases in the contralateral dorsal horn segments. The data demonstrate that widespread activation of spinal, especially dorsal horn, neurons following peripheral insult can occur in the injured spinal cord, despite reduced pain responsiveness, and suggests that exaggerated pain may emerge as spinal recovery or repair progresses. (c) 2007 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.