Acupuncture and Moxibustion College, Fujian University of Traditional Chinese Medicine, Fuzhou 350122, China.
Key Laboratory of Integrated Acupuncture and Drugs Constructed by the Ministry of Education and Jiangsu Province, Nanjing University of Chinese Medicine, Nanjing 210023.
Zhen Ci Yan Jiu. 2023 Oct 25;48(10):1017-1024. doi: 10.13702/j.1000-0607.20221021.
To investigate the effect of manual acupuncture at "Shangjuxu"(ST37) on nerve growth factor(NGF)/phosphatidylinositol 3-kinase(PI3K)/transient receptor potential vanilloid 1(TRPV1) signaling pathway in rats with chronic visceral hyperalgesia of irritable bowel syndrome (IBS), so as to explore its underlying mechanism in treating IBS chronic visceral hyperalgesia.
IBS chronic visceral hyperalgesia model was established by colorectal dilation stimulation for 2 weeks for SD pups at 8 d after birth, which were fed until 8-week age after the stimulation. Then the verified successfully modeled adult rats were randomly divided into model, Shangjuxu, and non-acupoint groups, with 6 rats in each group, and 6 unmodeled rats were selected as normal group. On the next day of model evaluation, rats in the Shangjuxu group received acupuncture at right ST37 while rats in the non-acupoint group received acupuncture at the non-meridian and non-acupoint point in the right hypochondrium, both for 15 min, with manual twisting of mild reinforcing and reducing performed for 30 s at an interval of 5 min, once a day, for a total of 7 d. Abdominal withdrawal reflex(AWR) score was used to evaluate the degree of chronic visceral pain in rats. Western blot and real-time fluorescence quantitative PCR were used to detect the colonic protein and mRNA expressions of NGF, tropomyosin receptor kinase A (TrkA), PI3K and TRPV1. The positive expressions of PI3K and TRPV1 proteins in the colon of rats were detected by immunohistochemistry method.
Compared with the normal group, AWR scores corresponding to 4 pressure levels of 20, 40, 60 and 80 mm Hg, mRNA and protein expressions of NGF, TrkA, PI3K and TRPV1 in colon tissue, and positive expressions of PI3K and TRPV1 in colon tissue were significantly increased(<0.05) in the model group. After intervention, compared with the model group, rats in the Shangjuxu group had reduced AWR scores corresponding to 4 pressure levels of 20, 40, 60 and 80 mm Hg, lower colonic mRNA and protein expressions of NGF, TrkA, PI3K and TRPV1, and decreased positive expressions of PI3K and TRPV1 in colon tissue(<0.05), while there were no significant differences in the above indexes of the non-acupoint group.
Manual acupuncture at ST37 can alleviate IBS chronic visceral hyperalgesia in rat and its analgesic effect may be related to regulating NGF/PI3K/TRPV1 signaling pathway.
观察针刺手三里穴对肠易激综合征（IBS）慢性内脏痛大鼠神经生长因子（NGF）/磷酸肌醇 3-激酶（PI3K）/瞬时受体电位香草酸 1 型（TRPV1）信号通路的影响，探讨其治疗 IBS 慢性内脏痛的作用机制。
采用新生 8 日龄 SD 大鼠结直肠扩张刺激法建立 IBS 慢性内脏痛模型，刺激结束后继续饲养至 8 周龄。造模成功后将大鼠随机分为模型组、手三里组和非经非穴组，每组 6 只，另设 6 只未造模大鼠为正常组。模型评价次日，手三里组大鼠右侧手三里穴针刺，非经非穴组大鼠右侧季肋区非经非穴点针刺，均捻转补法 15 min，每 5 min 行针 1 次，行针 30 s，每日 1 次，共 7 天。采用腹壁回缩反射（AWR）评分评价大鼠慢性内脏痛程度，Western blot 和实时荧光定量 PCR 检测结肠组织 NGF、原肌球蛋白受体激酶 A（TrkA）、PI3K 和 TRPV1 蛋白及 mRNA 表达，免疫组化法检测大鼠结肠组织中 PI3K 和 TRPV1 蛋白的阳性表达。
与正常组比较，模型组大鼠 20、40、60、80 mm Hg 压力时的 AWR 评分，结肠组织 NGF、TrkA、PI3K、TRPV1 蛋白及 mRNA 表达，以及结肠组织中 PI3K 和 TRPV1 蛋白的阳性表达均显著升高（P<0.05）；与模型组比较，手三里组大鼠各压力时的 AWR 评分降低，结肠组织 NGF、TrkA、PI3K、TRPV1 蛋白及 mRNA 表达降低，结肠组织中 PI3K 和 TRPV1 蛋白的阳性表达减少（P<0.05），而非经非穴组大鼠上述指标差异均无统计学意义。
针刺手三里穴可缓解 IBS 慢性内脏痛大鼠的内脏痛觉过敏，其镇痛作用可能与调节 NGF/PI3K/TRPV1 信号通路有关。
