Qiao Li-Na, Tan Lian-Hong, Yang Jiao-Jiao, Gao Qiao-Ling, Zhu Jiang, Rong Pei-Jing, Zhu Bing, Yang Yong-Sheng, Liu Jun-Ling
Institute of Acu-moxibustion, China Academy of Chinese Medical Sciences, Beijing 100700, China.
Institute of Acu-moxibustion, China Academy of Chinese Medical Sciences, Beijing 100700, China; Institute of Acupuncture and Massage, Changchun University of Traditional Chinese Medicine, Changchun 130117.
Zhen Ci Yan Jiu. 2017 Aug 25;42(4):283-9.
To observe the effect of electroacupuncture (EA) stimulation of "Futu"(LI 18), etc. on activities of satellite glial cells (SGCs) in the dorsal root ganglia (DRG) in rats with neck-incision pain so as to explore its mechanism underlying reduction of post-surgical pain of thyroidectomy.
Male SD rats were randomly divided into control, model, EA-Futu (LI 18), EA-Hegu (LI 4)-Neiguan (PC 6), and EA-Zusanli (ST 36)-Yanglingquan (GB 34) groups, with 20 rats in each group. The neck-incision pain model was established by making a longitudinal incision and repeated mechanical stimulation. In the EA-LI 18, EA-LI 4-PC 6 and EA-ST 36-GB 34 groups, EA stimulation was administrated for 30 min, once a day,continuously for 3 days. The thermal pain threshold (PT) of the neck-incision region was detected. The immunoactivity of glial fibrillary acidic protein (GFAP,a specific marker for SGCs) and connexin 43 (Cx 43) of DRGs (C 2-C 6) was determined by fluorescent immunohistochemistry. The expression levels of GFAP, IL-1 β, IL-6, and TNF-α mRNAs were determined by quantitative Real-time PCR, and the contents of IL-1 β,IL-6,TNF-α assayed by enzyme linked immunosorbent assay (ELISA) and the expression of Cx 43 protein was detected by Western blot.
After EA intervention at LI 18 and LI 4-PC 6 (but not ST 36-GB 34), neck incision-induced reduction of the thermal PT was obviously prolonged in comparison with the model group (<0.05),suggesting a pain relief. The expression levels of GFAP, IL-1 β, IL-6 and TNF-α mRNAs and Cx 43 protein, and the contents of IL-1 β, IL-6 and TNF-α in C 2-C 6 DRGs were all significantly up-regulated in the model group relevant to those of the control group (<0.05). Following EA, modeling induced dramatic increase of expression of GFAP, IL-1 β, IL-6 and TNF-α mRNAs and Cx 43 protein in both EA-LI 18 and EA-LI 4-PC 6 groups, and the contents of IL-1 β and TNF-α in the EA-LI 18 group, IL-6 in the EA-LI 4-PC 6 group was considerably down-regulated (<0.05). In comparison with the model group, no significant changes were found in all the abovementioned indexes of EA-ST 36 -GB 34 group except the down-regulated IL-1 β and TNF-α mRNAs, in the contents of IL-1 β and TNF-α of the EA-LI 4-PC 6 group, and in the IL-6 content of the EA-LI 18 group (>0.05).
EA stimulation of LI 18 and LI 4-PC 6 can significantly suppress pain reaction of neck incision in the rat, which is closely associated with its effects in down-regulating the activity of SGCs, decreasing the release of pro-inflammatory cytokines and in weakening the expression of Cx 43 in the cervical DRGs.
观察电针刺激“扶突”（LI 18）等穴位对颈部切口痛大鼠背根神经节（DRG）中卫星胶质细胞（SGCs）活性的影响，以探讨其减轻甲状腺切除术后疼痛的机制。
雄性SD大鼠随机分为对照组、模型组、电针扶突（LI 18）组、电针合谷（LI 4）-内关（PC 6）组、电针足三里（ST 36）-阳陵泉（GB 34）组，每组20只。通过纵行切口及反复机械刺激建立颈部切口痛模型。电针LI 18组、电针LI 4-PC 6组和电针ST 36-GB 34组，每天电针刺激30 min，连续3天。检测颈部切口区域的热痛阈（PT）。采用荧光免疫组织化学法检测DRGs（C 2-C 6）中胶质纤维酸性蛋白（GFAP，SGCs的特异性标志物）和连接蛋白43（Cx 43）的免疫活性。采用实时定量PCR法检测GFAP、IL-1β、IL-6和TNF-α mRNA的表达水平，采用酶联免疫吸附测定（ELISA）法检测IL-1β、IL-6、TNF-α的含量，采用蛋白质印迹法检测Cx 43蛋白的表达。
与模型组比较，电针LI 18组和电针LI 4-PC 6组（而非电针ST 36-GB 34组）干预后，颈部切口所致热痛阈降低明显延长（<0.05），提示疼痛缓解。与对照组比较，模型组C 2-C 6 DRGs中GFAP、IL-1β、IL-6和TNF-α mRNA及Cx 43蛋白的表达水平，以及IL-1β、IL-6和TNF-α的含量均显著上调（<0.05）。电针后，电针LI 18组和电针LI 4-PC 6组中建模诱导的GFAP、IL-1β、IL-6和TNF-α mRNA及Cx 43蛋白表达显著增加，电针LI 18组中IL-1β和TNF-α的含量、电针LI 4-PC 6组中IL-6的含量显著下调（<0.05）。与模型组比较，电针ST 36-GB 34组上述所有指标除IL-1β和TNF-α mRNA下调、电针LI 4-PC 6组中IL-1β和TNF-α的含量及电针LI 18组中IL-6的含量外，均无显著变化（>0.05）。
电针刺激LI 18和LI 4-PC 6可显著抑制大鼠颈部切口的疼痛反应，这与其下调颈部DRGs中SGCs活性、减少促炎细胞因子释放及减弱Cx 43表达密切相关。
