Department of Pharmacology, Faculty of Medicine of Ribeirão Preto, University of São Paulo, São Paulo 14049–900, Brazil.
Life Sci. 2012 Oct 29;91(17-18):837-42. doi: 10.1016/j.lfs.2012.08.032. Epub 2012 Sep 12.
This study evaluates the contribution of inhibitory pain pathways that descend to the spinal cord through the dorsolateral funiculus (DLF) on the effect of intrathecal gabapentin against spinal nerve ligation (SNL)-induced behavioral hypersensitivity to mechanical stimulation in rats.
Rats were submitted to a sham or complete ligation of the right L5 and L6 spinal nerves and a sham or complete DLF lesion. Next, the changes induced by intrathecal administration of gabapentin on the paw withdrawal threshold of rats to mechanical stimulation were evaluated electronically.
Intrathecal gabapentin (200μg/5μl) that was injected 2 or 7days after surgery fully inhibited the SNL-induced behavioral hypersensitivity to mechanical stimulation in sham DLF-lesioned rats; gabapentin was effective against the SNL-induced behavioral hypersensitivity to mechanical stimulation also in DLF-lesioned rats.
The effect of intrathecally administered gabapentin against SNL-induced behavioral hypersensitivity to mechanical stimulation in rats does not depend on the activation of nerve fibers that descend to the spinal cord via the DLF.
本研究通过评估通过背外侧束（DLF）下行至脊髓的抑制性疼痛通路对鞘内给予加巴喷丁抑制大鼠脊髓结扎（SNL）引起的机械刺激行为超敏反应的影响来评价。
大鼠接受假手术或右侧 L5 和 L6 脊神经的完全结扎以及假手术或完全 DLF 损伤。然后，通过电子方式评估鞘内给予加巴喷丁对大鼠机械刺激引起的足部撤回阈值的变化。
术后 2 或 7 天鞘内给予加巴喷丁（200μg/5μl）完全抑制了 sham DLF 损伤大鼠的 SNL 引起的机械刺激行为超敏反应；加巴喷丁对 DLF 损伤大鼠的 SNL 引起的机械刺激行为超敏反应也有效。
鞘内给予加巴喷丁对大鼠 SNL 引起的机械刺激行为超敏反应的抑制作用不依赖于通过 DLF 下行至脊髓的神经纤维的激活。
