【目的】观察髓核源性坐骨神经痛大鼠模型中背根神经节磷酸化p38丝裂原活化蛋白激酶(p-p38MAPK)表达的变化及其与炎性反应和机械痛敏的关系,以探讨腰椎间盘突出症的病理机制。【方法】选择成年SD雄性大鼠66只随机分为空白组(12只)、假...【目的】观察髓核源性坐骨神经痛大鼠模型中背根神经节磷酸化p38丝裂原活化蛋白激酶(p-p38MAPK)表达的变化及其与炎性反应和机械痛敏的关系,以探讨腰椎间盘突出症的病理机制。【方法】选择成年SD雄性大鼠66只随机分为空白组(12只)、假手术组(18只)和模型组(36只)。模型组在左腰5神经背根神经节(L5DRG)自体髓核移植以建立大鼠非压迫性腰椎间盘突出模型,假手术组自体肌肉移植。空白组不进行手术。测量各组大鼠术前至术后21 d的左后肢50%机械性撤足阈值(50%PWT)以测定机械痛敏的变化,空白组、假手术组术后7 d及模型组术后7、14、21 d各12只大鼠取左腰5DRG用免疫组化法测定环氧化酶-2(COX-2)与p-p38MAPK的阳性细胞比率。【结果】假手术组50%PWT术后无明显变化,模型组术后7 d出现明显的50%PWT下降损伤,术后14 d达最低值,术后21 d部分恢复;空白组、假手术组术后7 dDRG的COX-2和p-p38MAPK微弱表达,模型组术后7 d DRG的COX-2和p-p38MAPK高表达,模型组术后14 d DRG的COX-2和p-p38MAPK表达更高,模型组术后21 d DRG的COX-2和p-p38MAPK表达减弱。【结论】背根神经节的p-p38MAPK的表达与非压迫性髓核所致炎性反应和坐骨神经病理性神经痛的变化密切相关。展开更多
As sciatica and low back pain are among the most common medical complaints, many studies have duplicated these conditions in animals. Chronic compression of the dorsal root ganglion （CCD） is one of these models. The...As sciatica and low back pain are among the most common medical complaints, many studies have duplicated these conditions in animals. Chronic compression of the dorsal root ganglion （CCD） is one of these models. The surgery is simple： after exposing the L4/L5 intervertebral foramina, stainless steel rods are implanted unilaterally, one rod for each vertebra, to chronically compress the lumbar dorsal root ganglion （DRG）. Then, CCD can be used to simulate the clinical conditions caused by stenosis, such as a laterally herniated disc or foraminal stenosis. As the intraforaminal implantation of a rod results in neuronal somal hyperexcitability and spontaneous action potentials associated with hyperalgesia, spontaneous pain, and mechanical allodynia, CCD provides an animal model that mimics radicular pain in humans. This review concerns the mechanisms of neuronal hyperexcitability, focusing on various patterns of spontaneous discharge including one possible pain signal for mechanical allodynia - evoked bursting. Also, new data regarding its significant property of maintaining peripheral input are also discussed. Investigations using this animal model will enhance our un-derstanding of the neural mechanisms for low back pain and sciatica. Furthermore, the peripheral location of the DRG fa-cilitates its use as a locus for controlling pain with minimal central effects, in the hope of ultimately uncovering analgesics that block neuropathic pain without influencing physiological pain.展开更多
文摘【目的】观察髓核源性坐骨神经痛大鼠模型中背根神经节磷酸化p38丝裂原活化蛋白激酶(p-p38MAPK)表达的变化及其与炎性反应和机械痛敏的关系,以探讨腰椎间盘突出症的病理机制。【方法】选择成年SD雄性大鼠66只随机分为空白组(12只)、假手术组(18只)和模型组(36只)。模型组在左腰5神经背根神经节(L5DRG)自体髓核移植以建立大鼠非压迫性腰椎间盘突出模型,假手术组自体肌肉移植。空白组不进行手术。测量各组大鼠术前至术后21 d的左后肢50%机械性撤足阈值(50%PWT)以测定机械痛敏的变化,空白组、假手术组术后7 d及模型组术后7、14、21 d各12只大鼠取左腰5DRG用免疫组化法测定环氧化酶-2(COX-2)与p-p38MAPK的阳性细胞比率。【结果】假手术组50%PWT术后无明显变化,模型组术后7 d出现明显的50%PWT下降损伤,术后14 d达最低值,术后21 d部分恢复;空白组、假手术组术后7 dDRG的COX-2和p-p38MAPK微弱表达,模型组术后7 d DRG的COX-2和p-p38MAPK高表达,模型组术后14 d DRG的COX-2和p-p38MAPK表达更高,模型组术后21 d DRG的COX-2和p-p38MAPK表达减弱。【结论】背根神经节的p-p38MAPK的表达与非压迫性髓核所致炎性反应和坐骨神经病理性神经痛的变化密切相关。
基金supported by the National Natural Science Foundation of China(30870829)
文摘As sciatica and low back pain are among the most common medical complaints, many studies have duplicated these conditions in animals. Chronic compression of the dorsal root ganglion （CCD） is one of these models. The surgery is simple： after exposing the L4/L5 intervertebral foramina, stainless steel rods are implanted unilaterally, one rod for each vertebra, to chronically compress the lumbar dorsal root ganglion （DRG）. Then, CCD can be used to simulate the clinical conditions caused by stenosis, such as a laterally herniated disc or foraminal stenosis. As the intraforaminal implantation of a rod results in neuronal somal hyperexcitability and spontaneous action potentials associated with hyperalgesia, spontaneous pain, and mechanical allodynia, CCD provides an animal model that mimics radicular pain in humans. This review concerns the mechanisms of neuronal hyperexcitability, focusing on various patterns of spontaneous discharge including one possible pain signal for mechanical allodynia - evoked bursting. Also, new data regarding its significant property of maintaining peripheral input are also discussed. Investigations using this animal model will enhance our un-derstanding of the neural mechanisms for low back pain and sciatica. Furthermore, the peripheral location of the DRG fa-cilitates its use as a locus for controlling pain with minimal central effects, in the hope of ultimately uncovering analgesics that block neuropathic pain without influencing physiological pain.
