Cha Myeounghoon, Lee Kyuhong, Lee Chulhyun, Cho Jee-Hyun, Cheong Chaejoon, Sohn Jin-Hun, Lee Bae Hwan
Department of Physiology, Brain Korea PLUS Project for Medical Science, Brain Research Institute, Epilepsy Research Institute, Yonsei University College of Medicine, Seoul 03722, Republic of Korea.
Bioimaging Research Team, Korea Basic Science Institute, Ochang 28119, Republic of Korea.
Neurosci Lett. 2016 Feb 2;613:13-8. doi: 10.1016/j.neulet.2015.11.027. Epub 2015 Dec 28.
As imaging technology develops, magnetic resonance imaging (MRI) has furthered our understanding of brain function by clarifying the anatomical structure and generating functional imaging data related to information processing in pain conditions. Recent studies have reported that manganese (Mn(2+))-enhanced MRI (MEMRI) provides valuable information about the functions of the central nervous system. The aim of this study was to identify specific brain regions activated during noxious electric stimulation using high-resolution MEMRI. Male Sprague Dawley rats were divided into three groups: naïve, sham electrical stimulation, and noxious electric stimulation. Under urethane with α-chloralose mixture anesthesia, a catheter was placed in the external carotid artery to administrate 20% mannitol and manganese chloride (25mM MnCl2). Noxious electric stimulation (2Hz, 10V) was applied to the hind paw with a needle electrode. Stimulation-induced neuronal activation was detected using 4.7-T MRI. In response to noxious electrical stimulation, remarkable Mn(2+)-enhanced signals were observed in the agranular insular cortex, auditory cortex, primary somatosensory cortex of the hind limb, and granular and dysgranular insular cortex, which correspond to sensory tactile electric stimulus to the hindpaws. These results indicate that the combination of MEMRI with activity-induced Mn(2+)-dependent contrast can delineate functional areas in the rat brain.
随着成像技术的发展，磁共振成像（MRI）通过阐明解剖结构并生成与疼痛状态下信息处理相关的功能成像数据，进一步加深了我们对脑功能的理解。最近的研究报道，锰（Mn(2+)）增强磁共振成像（MEMRI）能提供有关中枢神经系统功能的有价值信息。本研究的目的是使用高分辨率MEMRI识别有害电刺激期间激活的特定脑区。将雄性Sprague Dawley大鼠分为三组：未处理组、假电刺激组和有害电刺激组。在乌拉坦与α-氯醛糖混合麻醉下，将导管插入颈外动脉以给予20%甘露醇和氯化锰（25mM MnCl2）。用针电极对后爪施加有害电刺激（2Hz，10V）。使用4.7-T MRI检测刺激诱导的神经元激活。响应有害电刺激时，在无颗粒岛叶皮质、听觉皮质、后肢初级体感皮质以及颗粒和颗粒下岛叶皮质中观察到明显的Mn(2+)增强信号，这些区域对应于后爪的感觉触觉电刺激。这些结果表明，MEMRI与活动诱导的Mn(2+)依赖性对比相结合可以描绘大鼠脑中的功能区域。
