Mediation of spinal nerve injury induced tactile allodynia by descending facilitatory pathways in the dorsolateral funiculus in rats
Mediation of spinal nerve injury induced tactile allodynia by descending facilitatory pathways in the dorsolateral funiculus in rats
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DOI：
10.1016/s0304-3940(00)01338-0
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发表时间：
2000-08-25
影响因子：
2.5
通讯作者：
Porreca, F
中科院分区：
文献类型：
--
作者：
Ossipov, MH;Sun, H;Porreca, F
有证据表明，周围神经损伤引起的触觉异常痛主要集中在棘上部位，而不是脊柱部位。在本实验中，我们探讨了通过背外侧索(DLF)阻断下行通路可能改变神经损伤引起的触觉异常痛的表达的可能性。雄性SD大鼠采用L-5/L-6脊神经结扎术。损毁DLF至SNL的同侧或对侧，通过测量von Frey纤维探查的抽离阈值来判断触觉异常。DLF损毁大鼠未表现出明显的运动障碍，酸不改变假SNL手术大鼠的感觉阈值。损毁SNL同侧的DLF可完全阻断SNL大鼠的触觉超敏反应。对侧DLF损毁和假手术对SNL诱导的痛觉异常没有任何影响。这些结果表明，周围神经损伤后的触觉超敏依赖于脊髓上节段性强直激活的净下行易化作用，支持下行易化作用的强直激活是慢性疼痛的基础的假说。(C)2000爱思唯尔爱尔兰科学有限公司。保留所有权利。
Evidence exists to indicate that tactile allodynia arising from peripheral nerve injury is integrated predominately at supraspinal, rather than spinal, sites. In the present experiments, the possibility that disruption of descending pathways through the dorsolateral funiculus (DLF) might alter expression of nerve-injury induced tactile allodynia was explored. Male, Sprague-Dawley rats received L-5/L-6 spinal nerve ligation (SNL). Lesions to the DLF were made ipsilateral or contralateral to SNL, Tactile allodynia was determined by measuring withdrawal thresholds to probing with von Frey filaments. Rats with DLF lesions presented no apparent motor deficits acid did not alter sensory threshold in sham-SNL operated rats. DLF lesions made ipsilateral to SNL completely blocked tactile allodynia in SNL rats. Contralateral DLF lesions and sham surgery did not have any effect on SNL-induced allodynia. These results indicate that tactile allodynia after peripheral nerve injury is dependent upon tonic activation of net descending facilitation from supraspinal sites and support the hypothesis of tonic activation of descending facilitation as a basis for chronic pain. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.