OBJECTIVE: To investigate the effect of electroacupuncture (EA) on Rho/Rho-associated coiled-coil-forming kinases (ROCK) signaling pathway of uterus tissue in rats with dysmenorrhea, so as to explore the underlying mechanism of EA treating primary dysmenorrhea (PD) and uterine smooth muscle
spasm, and to observe whether there is a difference in the effect of meridian acupoints in Conception Vessel (CV) and Governer Vessel (GV).
METHODS: Sixty female SD rats were randomly divided into saline, model, CV, GV, and non-acupoint groups, with 12 rats in each group. The dysmenorrhea model was established by subcutaneous injection of estradiol diphenhydrate combined with intraperitoneal injection of oxytocin (OT). EA (2 Hz) was applied to \"Qihai\" (CV6) and \"Zhongji\" (CV3) for CV group, \"Mingmen\" (GV4) and \"Yaoshu\" (GV2) for GV group, \"non-acupoint 1\" and \"non-acupoint 3\" on the left side for non-acupoint group, and manual acupuncture was applied to \"Guanyuan\" (CV4) for CV group, \"Yaoyangguan\" (GV3) for GV group, \"non-acupoint 2\" on the left side for non-acupoint group. The treatment was conducted for 20 min each time, once daily for 10 days. The writhing score was evaluated. The smooth myoelectric signals of rats\' uterus in vivo were recorded by multi-channel physiological recorder. The uterine histopathological changes were observed by HE staining. The contents of prostaglandin F2α (PGF2α), OT and calcium ion (Ca2+) in uterine tissue of rats were detected by ELISA. The protein and mRNA expression levels of smooth muscle 22-α (SM22-α), RhoA and ROCKⅡ in uterine tissue were detected by Western blot and fluorescence quantitative PCR, respectively.
RESULTS: Compared with the saline group, the writhing score of rats in the model group was increased (P<0.01), the amplitude voltage of uterine smooth muscle in vivo was elevated (P<0.01), the contents of PGF2α, OT and Ca2+, the protein and mRNA expression of SM22-α, RhoA and ROCK Ⅱ in uterine tissue were all increased (P<0.01). Compared with the model and the non-acupoint groups, the writhing scores of the CV and the GV groups were decreased (P<0.01, P<0.05), the amplitude voltage of uterine smooth muscle was decreased (P<0.01), the contents of PGF2α, OT and Ca2+ in uterine tissue were decreased (P<0.01, P<0.05), and the protein expression and mRNA expression of SM22-α, RhoA and ROCKⅡ in uterine tissue were decreased (P<0.01, P<0.05). HE staining showed extensive exfoliation of uterine intima with severe edema and increased glandular secretion in the model group, which was alleviated in the CV and GV groups.
CONCLUSIONS: EA at acupoints of CV and GV can significantly reduce the writhing score, uterine smooth muscle amplitude voltage, pathological injury degree of uterus, and relieve
spasm of uterine smooth muscle in dysmenorrhea rats, which may be related to its effect in regulating PGF2α and OT contents, inhibiting the Rho/ROCK signaling pathway, and reducing the SM22-α, RhoA, ROCKⅡ protein and mRNA expression, and Ca2+ content in uterine tissue.
目的: 基于Rho/Rho激酶(ROCK)信号通路,探讨电针任、督二脉经穴缓解子宫平滑肌痉挛、改善原发性痛经(PD)的作用机制并观察任、督二脉经穴作用是否存在差异。方法: SD雌性大鼠随机分为盐水组、模型组、任脉组、督脉组及非经非穴组,每组12只。采用苯甲酸雌二醇联合缩宫素(OT)建立类痛经大鼠模型。任脉组电针“气海”“中极”并针刺“关元”,督脉组电针“命门”“腰俞”并针刺“腰阳关”,非经非穴组电针左侧“非穴1”“非穴3”并针刺“非穴2”,每次20 min,1次/d,连续10 d。观察各组大鼠腹腔注射OT(2 U/只) 30 min内的扭体反应;多导生理记录仪记录大鼠在体子宫平滑肌电信号,HE染色法观察大鼠子宫组织的病理形态变化;ELISA法检测大鼠子宫组织前列腺素F2α(PGF2α)、OT、钙离子(Ca2+)的含量,Western blot及荧光定量PCR 法检测子宫组织平滑肌22-α(SM22-α)、RhoA、ROCKⅡ蛋白及mRNA表达水平。结果: 与盐水组比较,模型组大鼠扭体评分升高(P<0.01),在体子宫平滑肌振幅电压升高(P<0.01),HE染色可见子宫内膜大范围剥脱伴有严重的水肿,且腺体分泌增加,子宫组织中PGF2α、OT、Ca2+含量升高(P<0.01),子宫组织SM22-α、RhoA、ROCKⅡ的蛋白及mRNA的表达升高(P<0.01)。与模型组和非经非穴组比较,任脉组、督脉组扭体评分均降低(P<0.01,P<0.05),子宫平滑肌振幅电压降低(P<0.01),子宫内膜水肿程度较轻,腺体分泌减少,子宫组织中PGF2α、OT、Ca2+的含量降低(P<0.01,P<0.05),子宫组织SM22-α、RhoA、ROCKⅡ的蛋白及mRNA的表达降低(P<0.01,P<0.05)。结论: 电针任脉、督脉经穴均可降低类痛经大鼠的扭体评分、子宫平滑肌振幅电压、子宫病理损伤程度,缓解子宫平滑肌的痉挛。其机制可能与通过调控子宫组织PGF2α、OT含量,抑制子宫组织Rho/ROCK信号通路,降低SM22-α、RhoA、ROCKⅡ蛋白与mRNA表达及Ca2+含量有关。.