Research Center of Meridians, Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing 100700, China.
Research Center of Meridians, Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing 100700, China.
Neuropeptides. 2019 Oct;77:101957. doi: 10.1016/j.npep.2019.101957. Epub 2019 Jul 23.
Irritable bowel syndrome patients frequently complain of pain in body regions somatotopically distinct from the gut, suggesting the involvement of an exaggerated signaling process in both visceral and somatic sensory pathways. Increasing evidence has shown that sprouting of tyrosine hydroxylase immunoreactive (TH-IR) fibers toward sensory neurons in dorsal root ganglia maintains and exacerbates the neuropathic and inflammatory pain, as well as colonic inflammation. The aim of the present study was to determine whether electroacupuncture could alleviate the visceral and secondary somatic hyperalgesia in colitis rats by suppressing the TH-IR expression in related dorsal root ganglia. After trinitrobenzene sulfonic acid irritation, rats developed inflammatory tissue damage in the distal colon, which was accompanied by visceral hypersensitivity and secondary hind paw hyperalgesia, as indicated by enhanced visceromotor response to colorectal distension and decreased mechanical and thermal withdrawal latency of the hind paw. Additionally, excessive TH-IR fibers sprouted toward calcitonin gene-related peptide immunoreactive sensory neurons, and TH-IR neurons also increased in the sixth lumbar dorsal root ganglia of colitis rats. Both electroacupuncture and guanethidine attenuated visceral and referred hind paw hyperalgesia by inhibiting the over-expression of TH-IR neurons and fibers in the sixth lumbar dorsal root ganglia. Moreover local inflammatory damage in the distal colon was restored after 7 days of electroacupuncture intervention. These results suggest that electroacupuncture relieved visceral and referred hind paw hypersensitivity in colitis rats by inhibiting TH expression in the sixth lumbar dorsal root ganglia.
肠易激综合征患者经常会抱怨身体其他部位（与肠道在躯体感觉上存在差异的部位）的疼痛，这表明内脏和躯体感觉通路中的信号传递过程过度活跃。越来越多的证据表明，酪氨酸羟化酶免疫反应性（TH-IR）纤维向背根神经节感觉神经元的发芽维持并加剧了神经病理性和炎症性疼痛以及结肠炎症。本研究旨在确定电针对结肠炎症大鼠内脏和继发性躯体痛觉过敏的缓解作用是否通过抑制相关背根神经节中的 TH-IR 表达来实现。在三硝基苯磺酸刺激后，大鼠的远端结肠会发生炎症性组织损伤，这伴随着内脏敏感性和继发性后爪痛觉过敏，表现为对结直肠扩张的内脏运动反应增强和后爪机械和热缩足潜伏期降低。此外，过多的 TH-IR 纤维向降钙素基因相关肽免疫反应性感觉神经元发芽，并且结肠炎症大鼠的第六腰椎背根神经节中的 TH-IR 神经元也增加。电针和胍乙啶均可通过抑制第六腰椎背根神经节中 TH-IR 神经元和纤维的过度表达来减轻内脏和牵涉性后爪痛觉过敏。此外，电针干预 7 天后，远端结肠的局部炎症损伤得到恢复。这些结果表明，电针通过抑制第六腰椎背根神经节中的 TH 表达来缓解结肠炎症大鼠的内脏和牵涉性后爪过敏。
