通腑茯苓饮联合电针治疗大鼠骶上脊髓损伤后神经源性膀胱的作用机制研究

Mechanism of Tongfu Fuling Decoction combined with electroacupuncture in treating neurogenic bladder after suprasacral spinal cord injury in rats

摘要:

目的 探究通腑茯苓饮联合电针通过神经生长因子（NGF）-神经生长因子受体（TrkA）信号通路对大鼠骶上脊髓损伤（SSCI）后神经源性膀胱（NB）的影响及其作用机制。方法 采用随机数字表法将45只雌性大鼠分为对照组（8只）和实验组（37只）。实验组37只大鼠先复制SSCI模型，再复制SSCI后NB模型，其中5只大鼠模型复制失败，其余32只大鼠随机分为模型组、通腑茯苓饮组、电针组及联合组，每组8只。通腑茯苓饮组给予通腑茯苓饮6.25 g/（kg·d）灌胃处理；电针组对长强穴和维胞穴进行电针治疗，留针20 min，1次/d；联合组同时予以2种治疗；对照组与模型组给予等量的生理盐水，均连续治疗14 d。检测各组大鼠膀胱重量、残余尿量及尿流动力学指标，苏木精-伊红（HE）染色观察脊髓组织病理变化并进行病理学评分，实时荧光定量聚合酶链反应和Western blotting检测大鼠脊髓组织NGF、TrkA mRNA和蛋白的表达。结果 与对照组比较，模型组、通腑茯苓饮组、电针组及联合组大鼠膀胱重量、残余尿量增加，膀胱漏尿点压力、病理评分升高（P <0.05），膀胱顺应性降低，膀胱最大容量减少，NGF、TrkA mRNA和蛋白相对表达量降低（P <0.05）；与模型组比较，通腑茯苓饮组、电针组及联合组的膀胱重量、残余尿量减少，膀胱漏尿点压力、病理评分降低（P <0.05），膀胱顺应性升高，膀胱最大容量增加，NGF、TrkA mRNA和蛋白相对表达量升高（P <0.05）；与通腑茯苓饮组比较，电针组及联合组的膀胱重量、残余尿量减少，膀胱漏尿点压力、病理评分降低（P <0.05），膀胱顺应性升高，膀胱最大容量增加，NGF、TrkA mRNA和蛋白相对表达量升高（P <0.05）；与电针组比较，联合组的膀胱重量、残余尿量减少、膀胱漏尿点压力、病理评分降低（P <0.05），膀胱顺应性升高，膀胱最大容量增加，NGF、TrkA mRNA和蛋白相对表达量升高（P <0.05）。结论 通腑茯苓饮联合电针能改善SSCI后NB大鼠膀胱功能，其作用机制可能与NGF-TrkA信号通路有关。

Abstract:

Objective To explore whether Tongfu Fuling Decoction combined with electroacupuncture affects neurogenic bladder (NB) after suprasacral spinal cord injury (SSCI) through nerve growth factor (NGF)-tyrosine kinase (TrkA) signaling pathway in rats.Methods Eight rats were randomly selected as the control group by random number table method, and the remaining rats were used to establish the SSCI model followed by NB modeling, among which 5 rats were failed to establish the models. The rats successfully modelled were randomly divided into model group, Tongfu Fuling Decoction group, electroacupuncture group and combination group, with 8 rats in each group. The Tongfu Fuling Decoction group was given Tongfu Fuling Decoction at a dose of 6.25 g/(kg·d) by gavage. In the electroacupuncture group, acupuncture at Changqiang and Weibao acupoints was performed, and the needles were retained for 20 minutes, once a day. The combination group was given the two treatments at the same time. The control group and the model group were given the same amount of normal saline for 14 consecutive days. After treatment, bladder weight, residual urine volume, and urodynamics were detected. The histopathological changes in the spinal cord tissues were observed under H&E staining, and the pathological scores were evaluated. The mRNA and protein expressions of NGF and TrkA in spinal cord tissues of rats were detected by qRT-PCR and Western blotting, respectively.Results Compared with the control group, the bladder weight, residual urine volume, bladder leak point pressure, and the pathological score were increased, and the bladder compliance, the maximal bladder capacity, and the relative mRNA and protein expressions of NGF and TrkA were decreased in the model group, Tongfu Fuling Decoction group, electroacupuncture group and combination group (P < 0.05). Compared with the model group, the bladder weight, residual urine volume, bladder leak point pressure, and the pathological score were decreased, and bladder compliance, the maximal bladder capacity, and the relative mRNA and protein expressions of NGF and TrkA were increased in the Tongfu Fuling Decoction group, the electroacupuncture group and the combination group (P < 0.05). Compared with the Tongfu Fuling Decoction group, the bladder weight, residual urine volume, bladder leak point pressure, and the pathological score were decreased, and bladder compliance, the maximal bladder capacity, and the relative mRNA and protein expressions of NGF and TrkA were increased in the electroacupuncture group and the combination group (P < 0.05). Compared with the electroacupuncture group, the bladder weight, residual urine volume, bladder leak point pressure, and the pathological score were decreased, and bladder compliance, the maximal bladder capacity, and the relative mRNA and protein expressions of NGF and TrkA were increased in the combination group (P < 0.05).Conclusions Tongfu Fuling Decoction combined with electroacupuncture can improve the bladder function of rats with NB after SSCI, and its mechanisms may be related to the NGF-TrkA signaling pathway.