Short-term facilitation in the anterior cingulate cortex following stimulation of the medial thalamus in the rat
Short-term facilitation in the anterior cingulate cortex following stimulation of the medial thalamus in the rat
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DOI：
10.1016/j.brainres.2006.04.065
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发表时间：
2006-06-30
期刊：
影响因子：
2.9
通讯作者：
Shyu, Bai-Chuang
中科院分区：
文献类型：
--
作者：
Sun, Jyh-Jang;Kung, Jeng Chuang;Shyu, Bai-Chuang
本研究探讨了电成对脉冲刺激同侧内侧丘脑（MT）诱发的前扣带皮层（ACC）突触活动（场电位、多单位活动和汇源电流）的分布和定位。用氟烷（1.0-1.5%）麻醉雄性Sprague-Dawley大鼠，并将电配对脉冲刺激（100-300 μ A，脉冲间间隔，100 ms）递送至MT。用钨微电极和多通道Michigan探针记录ACC的诱发场电位和多单位活动。负场电位的第二个分量（com 2）增加到第一个分量（com 1）的约2.5倍，综合多单元活动促进了约1.6倍。配对刺激产生的最大负电位从层II/III到更深的层扣带回皮质区1（Cg 1）的扩展。此外，增强的活动扩散到相邻的次级运动皮层（M2）和前边缘皮层（PrL）。同时，在M2、Cg 1和PrL中，最大综合多单元活动覆盖的区域从第V层（com 1）扩展到第II-V层（com 2）。电流源密度（CSD）分析显示，短潜伏期汇位于II/III层和V/VI层。当第二个脉冲以100 ms的时间延迟传递时，灌电流被增强并扩展到更浅和更深层。灌流和成对脉冲易化（PPF）被吗啡处理（5 mg/kg，i. v.），纳洛酮可阻断这种作用。MT中10 Hz的电刺激诱导内侧前额叶皮层神经元的c-fos免疫标记比1 Hz刺激更明显。短时程易化发生在前扣带回的中层并扩展到深层，这些变化可能介导了与疼痛反应相关的特定频率的有效信号传递。(c)2006 Elsevier B. V.保留所有权利。
The present study examined the distribution and localization of synaptic activities (field potentials, multiunit activities and sink source currents) evoked in the anterior cingulate cortex (ACC) by electrical paired pulse stimulation of the ipsilateral medial thalamus (MT). Male Sprague-Dawley rats were anesthetized with halothane (1.0-1.5%), and electrical paired pulses stimuli (100-300 mu A, inter-pulse interval, 100 ms) were delivered to the MT. Tungsten microelectrodes and a multichannel Michigan probe were used to record the evoked field potentials and multiunit activities in the ACC. Paired pulse stimulation facilitated field potentials and multiunit activities elicited from several MT nuclei. The second component of the negative field potential (com2) was augmented to about 2.5 times that of the first component (com1), and the integrated multiunit activities were facilitated by about 1.6-fold. Paired stimulation produced an expansion of the maximal negative potential from layer II/III into the deeper layers of the cingulate cortex area 1 (Cg1). Furthermore, the potentiated activity spread into adjacent secondary motor cortex (M2) and prelimbic cortex (PrL). Meanwhile, the area covered by the maximal integrated multiunit activities expanded from layer V (com1) to layers II-V (com2) in M2, Cg1 and PrL. The current source density (CSD) analysis revealed that the short latency sinks were located in layer II/III and layer V/VI. The sink currents were potentiated and expanded to more superficial and to deeper layers when a second pulse was delivered with a 100-ms time delay. Sink currents and the paired pulse facilitation (PPF) were reduced by morphine treatment (5 mg/kg, i.v.), and this effect could be blocked by naloxone. Electrical stimulation at 10 Hz in the MT induced more pronounced c-fos immunolabeling of neurons in the medial prefrontal cortex than did 1-Hz stimulation. The short-term facilitation occurred in the middle layers and expanded to the deeper layers of the ACC. These changes may mediate the effective signal transference in the specific frequency associated with painful responses. (c) 2006 Elsevier B.V. All rights reserved.