PDF(Pubmed)
Abstract：
The cellular distribution and changes in CX3CL1/fractalkine and its receptor CX3CR1 protein levels in the trigeminal subnucleus caudalis (TSC) of rats with unilateral infraorbital nerve ligation (IONL) were investigated on postoperation days 1, 3, 7, and 14 (POD1, POD3, POD7, and POD14, respectively) and compared with those of sham-operated and naïve controls. Behavioral tests revealed a significant increase in tactile hypersensitivity bilaterally in the vibrissal pads of both sham- and IONL-operated animals from POD1 to POD7, with a trend towards normalization in sham controls at POD14. Image analysis revealed increased CX3CL1 immunofluorescence (IF) intensities bilaterally in the TSC neurons of both sham- and IONL-operated rats at all survival periods. Reactive astrocytes in the ipsilateral TSC also displayed CX3CL1-IF from POD3 to POD14. At POD1 and POD3, microglial cells showed high levels of CX3CR1-IF, which decreased by POD7 and POD14. Conversely, CX3CR1 was increased in TSC neurons and reactive astrocytes at POD7 and POD14, which coincided with high levels of CX3CL1-IF and ADAM17-IF. This indicates that CX3CL1/CX3CR1 may be involved in reciprocal signaling between TSC neurons and reactive astrocytes. The level of CatS-IF in microglial cells suggests that soluble CX3CL1 may be involved in neuron-microglial cell signaling at POD3 and POD7, while ADAM17 allows this release at all studied time points. These results indicate an extended CX3CL1/CX3CR1 signaling axis and its role in the crosstalk between TSC neurons and glial cells during the development of trigeminal neuropathic pain.
摘要：
在术后第1、3、7和14天（分别为POD1、POD3、POD7和POD14），研究了单侧眶下神经结扎（IONL）大鼠三叉神经尾核亚核（TSC）中CX3CL1/fractalkine及其受体CX3CR1蛋白水平的细胞分布和变化。行为测试表明，从POD1到POD7，假手术和IONL手术的动物的触感垫两侧的触觉敏感性显着增加，在POD14的假对照中有正常化的趋势。图像分析显示，在所有存活期，sham和IONL手术大鼠的TSC神经元中，双侧CX3CL1免疫荧光（IF）强度增加。同侧TSC中的反应性星形胶质细胞也显示从POD3到POD14的CX3CL1-IF。在POD1和POD3，小胶质细胞显示高水平的CX3CR1-IF，由POD7和POD14减少。相反，CX3CR1在POD7和POD14的TSC神经元和反应性星形胶质细胞中增加，这与CX3CL1-IF和ADAM17-IF的高水平一致。这表明CX3CL1/CX3CR1可能参与TSC神经元和反应性星形胶质细胞之间的相互信号传导。小胶质细胞中CatS-IF的水平表明，可溶性CX3CL1可能参与POD3和POD7的神经元-小胶质细胞信号传导，而ADAM17在所有研究的时间点都允许这种释放。这些结果表明CX3CL1/CX3CR1信号轴的延长及其在三叉神经性疼痛发展过程中TSC神经元和神经胶质细胞之间的串扰中的作用。
