Inhibitory coupling between inhibitory interneurons in the spinal cord dorsal horn.
Inhibitory coupling between inhibitory interneurons in the spinal cord dorsal horn.
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DOI：
10.1186/1744-8069-5-24
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发表时间：
2009-05-12
期刊：
影响因子：
3.3
通讯作者：
De Koninck Y
中科院分区：
文献类型：
--
作者：
Labrakakis C;Lorenzo LE;Bories C;Ribeiro-da-Silva A;De Koninck Y
背角的局部抑制性中间神经元在节段水平的兴奋性控制中发挥着重要作用，从而决定了伤害性信息如何传递到更高的结构。因此，抑制性中间神经元活动的调节可能对疼痛感知产生严重影响。事实上，背角神经元网络的去抑制破坏了兴奋和抑制之间的平衡，并且被认为是不同形式的疼痛超敏性和慢性疼痛状态的关键机制。在这种情况下，研究抑制性中间神经元接收的抑制性输入的来源和突触特性对于预测药物作用在网络水平上的影响非常重要。为了解决这个问题，我们研究了在视觉引导下从在 GAD 启动子控制下表达增强型绿色荧光蛋白 (EGFP) 的转基因小鼠脊髓切片中识别出的第二层抑制性中间神经元的抑制性突触传递。这些细胞中的大多数会发出长的去极化电流脉冲。这些细胞中的单突触诱发抑制性突触后电流 (eIPSC) 由 GABAA 和甘氨酸受体介导。与此一致的是，在所有细胞中都记录了 GABAA 和甘氨酸受体介导的微型 IPSC。这些抑制性输入至少部分源自局部第二层中间神经元，这一点通过一对 EGFP+ 细胞的同时记录得到证实。这些突触似乎具有较低的释放概率，并且在重复激活时表现出增强和异步释放。总之，我们报告了以前未经检查的背角电路的组成部分，该组成部分可能构成伤害感受微调的基本要素。
Local inhibitory interneurons in the dorsal horn play an important role in the control of excitability at the segmental level and thus determine how nociceptive information is relayed to higher structures. Regulation of inhibitory interneuron activity may therefore have critical consequences on pain perception. Indeed, disinhibition of dorsal horn neuronal networks disrupts the balance between excitation and inhibition and is believed to be a key mechanism underlying different forms of pain hypersensitivity and chronic pain states. In this context, studying the source and the synaptic properties of the inhibitory inputs that the inhibitory interneurons receive is important in order to predict the impact of drug action at the network level. To address this, we studied inhibitory synaptic transmission in lamina II inhibitory interneurons identified under visual guidance in spinal slices taken from transgenic mice expressing enhanced green fluorescent protein (EGFP) under the control of the GAD promoter. The majority of these cells fired tonically to a long depolarizing current pulse. Monosynaptically evoked inhibitory postsynaptic currents (eIPSCs) in these cells were mediated by both GABAA and glycine receptors. Consistent with this, both GABAA and glycine receptor-mediated miniature IPSCs were recorded in all of the cells. These inhibitory inputs originated at least in part from local lamina II interneurons as verified by simultaneous recordings from pairs of EGFP+ cells. These synapses appeared to have low release probability and displayed potentiation and asynchronous release upon repeated activation. In summary, we report on a previously unexamined component of the dorsal horn circuitry that likely constitutes an essential element of the fine tuning of nociception.
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影响因子：
5.5
作者：
Grudt, TJ;Perl, ER
通讯作者：
Perl, ER
影响因子：
5.3
作者：
Lu, Y;Perl, ER
通讯作者：
Perl, ER
影响因子：
2.5
作者：
Dougherty, KJ;Sawchuk, MA;Hochman, S
通讯作者：
Hochman, S
影响因子：
3.3
作者：
Keller AF;Beggs S;Salter MW;De Koninck Y
通讯作者：
De Koninck Y
影响因子：
3.5
作者：
Baba, H;Ji, RR;Woolf, CJ
通讯作者：
Woolf, CJ