Basic Research of low back pain

我们用大鼠研究了下腰痛的机制，并获得了以下结果。(1)下腰痛状态下脑和脊髓Fos表达：采用急性伤害性刺激大鼠腰肌（深度痛组）和皮肤（皮肤痛组），研究下腰痛状态下脑和脊髓Fos表达模式。在脊髓中，Fos免疫反应（Fos-ir）神经元没有观察到在板层II后，下背部肌肉刺激。在大脑中，Fors-ir神经元观察到的显着更大的数字在深部躯体疼痛组的丘脑，杏仁核基底外侧核，室旁下丘脑，和腹外侧导水管周围灰质比皮肤疼痛组。(2)P物质和降钙素基因相关肽免疫反应阳性的感觉背根神经节（DRG）神经元支配的腰椎小关节在大鼠：神经元支配L5/6小关节分布在整个DRG从L1到L5水平。L1和L2背根节SP和CGRP阳性神经元的比例明显低于L3、L4和L5背根节。在生理状态下，大鼠背根神经节下段神经元可能比上段神经元对面部痛觉的调节作用更大。(3)背根神经节神经元与小关节和坐骨神经的分叉轴突：我们证明了在大鼠存在的感觉神经元与小关节和坐骨神经的分叉轴突使用双标记方法。这个神经元为小关节疾病引起的牵涉性腿痛提供了一个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.