受压脊髓神经节中卫星神经胶质细胞的功能特性改变。

Altered functional properties of satellite glial cells in compressed spinal ganglia.

作者信息

Zhang Haijun, Mei Xiaofeng, Zhang Pu, Ma Chao, White Fletcher A, Donnelly David F, Lamotte Robert H

机构信息

Department of Anesthesiology, Yale University School of Medicine, New Haven, Connecticut 06510, USA.

出版信息

Glia. 2009 Nov 15;57(15):1588-99. doi: 10.1002/glia.20872.

Abstract

The cell bodies of sensory neurons in the dorsal root ganglion (DRG) are enveloped by satellite glial cells (SGCs). In an animal model of intervertebral foraminal stenosis and low-back pain, a chronic compression of the DRG (CCD) increases the excitability of neuronal cell bodies in the compressed ganglion. The morphological and electrophysiological properties of SGCs were investigated in both CCD and uninjured, control lumbar DRGs. SGCs responded within 12 h of the onset of CCD as indicated by an increased expression of glial fibrillary acidic protein (GFAP) in the compressed DRG but to lesser extent in neighboring or contralateral DRGs. Within 1 week, coupling through gap junctions between SGCs was significantly enhanced in the compressed ganglion. Under whole-cell patch clamp recordings, inward and outward potassium currents, but not sodium currents, were detected in individual SGCs. SGCs enveloping differently sized neurons had similar electrophysiological properties. SGCs in the compressed vs. control DRG exhibited significantly reduced inwardly rectifying potassium currents (Kir), increased input resistances and positively shifted resting membrane potentials. The reduction in Kir was greater for nociceptive medium-sized neurons compared to non-nociceptive neurons. Kir currents of SGCs around spontaneously active neurons were significantly reduced 1 day after compression but recovered by 7 days. These data demonstrate rapid alterations in glial membrane currents and GFAP expression in close temporal association with the development of neuronal hyperexcitability in the CCD model of neuropathic pain. However, these alterations are not fully sustained and suggest other mechanisms for the maintenance of the hyperexcitable state.

摘要

背根神经节(DRG)中的感觉神经元细胞体被卫星神经胶质细胞(SGCs)包裹。在椎间孔狭窄和腰背痛的动物模型中,DRG的慢性压迫(CCD)会增加受压神经节中神经元细胞体的兴奋性。研究了CCD组和未受伤的对照腰段DRG中SGCs的形态和电生理特性。CCD开始后12小时内,SGCs就有反应,表现为受压DRG中胶质纤维酸性蛋白(GFAP)表达增加,但在相邻或对侧DRG中程度较轻。1周内,受压神经节中SGCs之间通过缝隙连接的耦合显著增强。在全细胞膜片钳记录下,在单个SGCs中检测到内向和外向钾电流,但未检测到钠电流。包裹不同大小神经元的SGCs具有相似的电生理特性。受压DRG与对照DRG中的SGCs相比,内向整流钾电流(Kir)显著降低,输入电阻增加,静息膜电位正向偏移。与非伤害性神经元相比,伤害性中等大小神经元的Kir降低幅度更大。受压后1天,自发活动神经元周围SGCs的Kir电流显著降低,但7天后恢复。这些数据表明,在神经性疼痛的CCD模型中,胶质细胞膜电流和GFAP表达迅速改变,与神经元兴奋性过高的发展密切相关。然而,这些改变并未完全持续,提示存在维持兴奋性过高状态的其他机制。

文献AI研究员

20分钟写一篇综述,助力文献阅读效率提升50倍

立即体验

用中文搜PubMed

大模型驱动的PubMed中文搜索引擎

马上搜索