Basic Research of low back pain

我们对大鼠腰痛机制进行了研究，得到以下结果：(1)腰痛状态下Fos在脑和脊髓中的表达：采用急性有害刺激大鼠腰肌（深痛组）和皮肤（皮痛组），研究Fos在脑和脊髓中的表达规律。在脊髓中，刺激下背部肌肉后，在II层未观察到Fos-ir神经元。在大脑中，深度躯体疼痛组伏隔核、杏仁核基底外侧核、室旁下丘脑和腹外侧导水管周围灰质中Fors-ir神经元的数量明显高于皮肤疼痛组。(2)支配大鼠腰椎小关节的P物质和降钙素基因相关肽免疫反应性感觉背根神经节（DRG）神经元：支配L5/6小关节的神经元分布于DRG的L1至L5水平。SP和CGRP-ir神经元在l1和L2 DRGs中的比例明显低于L3、L4和L5 DRGs。在大鼠生理状态下，下DRG神经元可能比上DRG神经元在面部疼痛感觉中发挥更重要的作用。(3)小关节和坐骨神经轴突分化的DRG神经元：采用双标记法在大鼠身上证实了小关节和坐骨神经轴突分化的感觉神经元的存在。该神经元为小关节疾病的牵涉性腿痛提供了可能的神经解剖学基础。

We studied the mechanism of low back pain using rats, and obtained the following results.(1) Fos expression in the brain and spinal cord in condition of low back pain : Acute noxious stimulation delivered to lumbar muscles (deep pain group) and skin (cutaneous pain group) of rats was used to study Fos expression patterns in the brain and spinal cord. In the spinal cord, Fos-immunoreactive (Fos-ir) neurons were not observed in the lamina II after stimulation of low back muscles. In the brain, Fors-ir neurons were observed in significantly greater numbers in the deep somatic pain group in the accumbens, basolateral nucleus of amygdala, paraventricular hypothalamus, and the ventrolateral periaqueductal gray than in the cutaneous pain group.(2) Substance P and Calcitonin Gene-Related Peptide immunoreactive sensory dorsal root ganglion (DRG)neurons innervating the lumbar facet joints in rats : Neurons innervating the L5/6 facet joint were distributed throughout DRGs from L1 to L5 levels. The ratios of SP and CGRP-ir neurons inL1 and L2 DRGs were significantly less than those in L3, L4 or L5 DRGs. In the physiological condition in rats, lower DRG neurons may have a more significant role in pain sensation of the facests than upper DRG neurons.(3) DRG neurons with dichotomizing axons to the facet joint and sciatic nerve : We demonstrated in rats the existence of the sensory neuron with dichotomizing axons both to the facet joint and the sciatic nerve using double-labelling method. This neuron provides a possible neuro-anatomical substratum for referred leg pain in facet joint disease.