Secondary hyperalgesia in the monoarthritic rat is mediated by GABAB and NK1 receptors of spinal dorsal horn neurons:: A behavior and c-fos study
Secondary hyperalgesia in the monoarthritic rat is mediated by GABAB and NK1 receptors of spinal dorsal horn neurons:: A behavior and c-fos study
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DOI：
10.1016/j.neuroscience.2006.05.048
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发表时间：
2006-01-01
期刊：
影响因子：
3.3
通讯作者：
Tavares, I.
中科院分区：
文献类型：
--
作者：
Castro, A. R.;Pinto, M.;Tavares, I.
在单关节炎大鼠中继发性痛觉过敏伴随着表达GABA（B）受体的脊髓神经元的伤害性激活的减少和表达神经激肽1（NK 1）受体的细胞中的相反效应。为了确定每个受体的相对作用，鞘内施用SP-皂草素（SP-SAP）、巴氯芬或两者的作用使用继发性痛觉过敏模型进行评估，所述继发性痛觉过敏模型由靠近发炎关节的后肢皮肤的机械刺激组成。通过关节内注射完全弗氏佐剂（CFA）诱导单关节炎后4天，在T-13-L-1水平植入套管，并鞘内（i.t.）注射。CFA注射后14天，每组中一半动物接受10 μ l生理盐水的L.注射，其余动物注射相同体积。巴氯芬（1 μ g）。10分钟后，通过von Frey测试对动物进行行为评估，或进行有害的机械刺激以分析c-fos表达。治疗后von Frey阈值增加，但巴氯芬或SP-SAP+巴氯芬后更明显。在L-2-L-3节段（接受来自炎症关节附近刺激皮肤的输入的脊髓区域），在三种治疗后，浅背角和深背角中的Fos免疫反应阳性神经元的数量都减少。在T-13-L-1节段，SP-SAP加巴氯芬处理后，背角两侧区Fos免疫反应阳性神经元数量显著减少，巴氯芬处理后，背角深部Fos免疫反应阳性神经元数量显著减少。我们的结论是，GABA（B）和NK 1受体的脊髓背角神经元参与继发性痛觉过敏在单关节炎大鼠，虽然减少GABA抑制似乎发挥更重要的作用比增加SP介导的效果。(c)2006 IBRO;由Elsevier Ltd.出版。保留所有权利。
Secondary hyperalgesia in the monoarthritic rat is accompanied by a decrease in nociceptive activation of spinal neurons expressing GABA(B) receptors and by the opposite effect in the cells expressing neurokinin 1 (NK1)-receptors. In order to ascertain the relative role of each receptor, the effects of intrathecal administration of SP-saporin (SP-SAP), baclofen or both were evaluated, using a model of secondary hyperalgesia that consists of mechanical stimulation of the hindlimb skin close to an inflamed joint. Four days after the induction of monoarthritis by intraarticular injection of Complete Freund's Adjuvant (CFA), a cannula was implanted at T-13-L-1 level and 10 mu l of saline or SP-SAP (10(-6) M) were intrathecally (i.t.) injected. Fourteen days after CFA-injection, half of the animals from each group received Lt. injections of 10 mu l saline and the remainder were injected with the same volume. of baclofen (1 mu g). Ten minutes later, the animals were behaviorally evaluated by the von Frey test or submitted to noxious mechanical stimulation to analyze c-fos expression. The von Frey thresholds increased after the treatments, but more pronouncedly after baclofen or SP-SAP plus baclofen. In segments L-2-L-3 the spinal area that receives input from the stimulated skin close to the inflamed joint, the numbers of Fos-immunoreactive neurons were reduced after the three treatments both in the superficial and deep dorsal horn. In segments T-13-L-1, the numbers of Fos-immunoreactive neurons were significantly reduced after treatment with SP-SAP plus baclofen in both dorsal horn regions, and in the deep dorsal horn after baclofen treatment. We conclude that both GABA(B) and NK1 receptors of spinal dorsal horn neurons participate in secondary hyperalgesia in the monoarthritic rat, although the decrease in GABA inhibition appears to play a more important role than the increase in SP-mediated effects. (c) 2006 IBRO; Published by Elsevier Ltd. All rights reserved.