Removal of GABAergic inhibition facilitates polysynaptic A fiber-mediated excitatory transmission to the superficial spinal dorsal horn
Removal of GABAergic inhibition facilitates polysynaptic A fiber-mediated excitatory transmission to the superficial spinal dorsal horn
复制标题
DOI：
10.1016/s1044-7431(03)00236-7
复制
发表时间：
2003-11-01
影响因子：
3.5
通讯作者：
Woolf, CJ
中科院分区：
文献类型：
--
作者：
Baba, H;Ji, RR;Woolf, CJ
初级传入A纤维刺激通常引起短持续时间的快速单突触或多突触EPSC。然而，在GABA（A）受体拮抗剂荷包牡丹碱的存在下，在初始的快速反应之后可以观察到重复的、持久的、多突触的EPSC。A-纤维诱导的ERK活化也在荷包牡丹碱的存在下促进。荷包牡丹碱或GABA（A）受体激动剂蝇蕈醇不影响微型EPSC的频率和单突触A纤维诱发的EPSC的振幅，表明位于兴奋性中间神经元的体树突部位的GABA（A）受体对该作用至关重要。荷包牡丹碱增强的多突触EPSC被NMDA受体拮抗剂APV和氯胺酮完全消除，增强的ERK激活也是如此。这种NMDA受体依赖的现象可能有助于荷包牡丹碱诱导的异常性疼痛或痛觉过敏，以及在神经性疼痛患者中观察到的超敏反应。(C)2003年爱思唯尔公司All rights reserved.
Primary afferent A-fiber stimulation normally evokes fast mono- or polysynaptic EPSCs of short duration. However, in the presence of the GABA(A) receptor antagonist bicuculline, repetitive, long lasting, polysynaptic EPSCs can be observed following the initial, fast response. A-fiber-induced ERK activation is also facilitated in the presence of bicuculline. The frequency of miniature EPSCs and the amplitude of the monosynaptic A-fiber-evoked EPSCs are not affected by bicuculline or the GABA(A) receptor agonist muscimol, suggesting that GABA(A) receptors located on somatodendritic sites of excitatory interneurons are critical for this action. Bicuculline-enhanced polysynaptic EPSCs are completely eliminated by NMDA receptor antagonists APV and ketamine, as was the augmented ERK activation. This NMDA receptor-dependent phenomenon may contribute to bicuculline-induced allodynia or hyperalgesia, as well as the hypersensitivity observed in neuropathic pain patients. (C) 2003 Elsevier Inc. All rights reserved.