基于L-VGCC通路对针刺调节妊娠晚期大鼠子宫平滑肌收缩的助产机制研究

Spontaneous labor is beneficial to maternal and child health. At present, machinery or drugs assisted labor technology may cause varies complications, thus finding a more safe and effective method of assisted delivery is a hotspot in obstetrics. Assisting delivery by acupuncture has a long history, and its clinical effect has been initially verified, however, it still lacks the systematic and definitive mechanism to support it. In previous studies, it has been found that acupuncture can activate IP3-dependent Ca2+ release in the uterine muscle cells of late pregnant rats, namely intracellular calcium store release. Therefore we hypothesized that acupuncture increases intracellular Ca2+ concentration to promote uterine contractions, through the intracellular/extracellular calcium release/ current. There is few study report about this. To confirm this hypothesis, this study will choose classic promoting delivery points-- " LI4(Hegu) –SP6(Sanyinjiao) " and electroacupuncture intervention. We will observe the effect of electroacupuncture on myometrial intracellular Ca2+ concentration in late pregnant rats, explore acupuncture mechanisms of promoting uterine contraction by Ca2+ pathway by using the MTB, molecular biology technology and other testing methods, and reveals the microscopic mechanism of acupuncture affect Ca2+ concentration through extracellular Ca2+ influx channel (L-VGCC channel ). This project aims to provide scientific evidence for acupuncture assisted labor, and help for clinical application, which promotes the development of labor health.

自然分娩有利于母婴健康，目前产科中常用的机械或药物助产技术均存在不同程度的并发症，寻找更安全、有效的辅助分娩方法仍是当今产科的热点。针灸助产历史悠久，其临床效应已得到初步验证，但尚缺乏系统、明确的机理阐释。前期研究发现，针刺可激活妊娠晚期大鼠子宫肌细胞IP3介导的胞内钙库释放通路。我们推测针刺通过对细胞内/外钙释放/内流通路的调节，上调胞内Ca2+浓度，进而产生促宫缩效应，而针刺助产对子宫肌Ca2+浓度的影响及其信号通路的研究，国内外尚无报道。为证实上述假说，本项目选用经典助产对穴“合谷-三阴交穴”，施以电针干预，通过MTB、分子生物学等检测方法，观察针刺对妊娠晚期大鼠子宫肌Ca2+浓度的影响，系统探讨针刺通过Ca2+途径促进宫缩的助产机制；并揭示针刺通过胞外Ca2+内流途径（L-VGCC通道）影响Ca2+浓度的微观机制。本项目为针刺助产提供科学证据，利于其临床推广，推动生殖健康发展。

针灸助产历史悠久，其临床效应已得到初步证实，但尚缺乏系统、明确的机理阐释，子宫收缩力是分娩时最主要产力，是研究针刺助产机制的重要切入点。本研究基于前期研究成果，采用优选的电针刺激参数针刺传统助产处方合谷-三阴交穴，并与催产素组、孕鼠模型组和雌鼠空白组进行效应指标的对比，通过对孕晚期大鼠子宫组织中雌二醇（E2）、孕酮（P）、前列腺素（PGF2α）和催产素（OT）的浓度及其受体（FP，OTR）表达的研究，探讨针刺影响大鼠子宫平滑肌收缩的作用途径。并通过对胞内Ca2+浓度和钙调蛋白激酶（CaMKII）表达的研究，阐明针刺通过影响胞内Ca2+介导的肌肉收缩途径而助产的分子生物学机制。为进一步探索针刺影响胞内Ca2+浓度的细胞内途径，增添Ca2+内流通道阻滞剂组进行以上效应指标的对比。研究发现针刺通过显著升高子宫组织内E2、PGF2α和OT的含量及降低P的含量，而显著提高子宫平滑肌细胞内Ca2+浓度，增强CaMKII的表达，且与有效剂量催产素（2.5IU/100g体重）效应相近，而L型电压门控钙通道（L-VGCC）阻滞剂维拉帕米则可以显著降低L-VGCC的表达，从而阻断针刺引起的胞内Ca2+大量聚集效应并导致CaMKII的表达下降。综合以上成果，本研究系统地阐明了针刺可通过对孕晚期大鼠子宫内分泌的调节作用，影响胞内Ca2+介导的子宫平滑肌收缩途径而产生促宫缩效应的助产机理，而针刺通过提高L-VGCC的活性而促进胞外Ca2+的大量内流则可能是针刺在细胞层面的促宫缩效应的重要机制。本项目的实施为针刺助产提供了系统、深入的科学证据，利于其临床推广，推动生殖健康发展。