【作者】 徐惠成；

【导师】 史常旭；

【作者基本信息】 第三军医大学 ， 外科学， 2005， 博士

【摘要】 女性压力性尿失禁(SUI)是指在腹压突然增加时出现无法控制的漏尿,SUI是一种妇科常见疾病,随人口老年化加重,其发病率越来越高。控尿的主动机制由膀胱颈部、尿道括约肌和尿道肌肉组织的主动收缩完成,这些肌肉的主动收缩产生使膀胱出口关闭的压力。导致SUI的关键机制主要有两种,尿道固有括约肌结构及功能缺陷和膀胱颈支撑功能障碍。其中尿道固有括约肌缺陷(ISD)是导致女性SUI的重要原因,特别是老年女性,几乎都有括约肌异常的因素。在女性,造成尿道括约肌功能缺陷的最主要原因是年老和产伤,分娩创伤和其他尿失禁的诱发因素,可使得支配相关肌肉的神经受到损害或肌肉本身损伤,从而使盆底肌和括约肌的质量和数量发生改变。正常机体局部肌肉组织损伤后会发生组织再生,由肌肉组织内的成肌细胞再生,以修复损伤的肌肉组织,但尿道括约肌的再生能力有限,在ISD患者存在有明显的成肌功能障碍。SUI的治疗方法众多,包括手术治疗和非手术治疗,由于这些方法均仅解决膀胱颈支撑功能障碍,不能纠正ISD,因此长期疗效不理想,且并发症多。特别是对由于ISD所致的SUI,由于成肌功能障碍的存在,传统的治疗方法疗效更差,从本质上改善ISD的治疗方法是纠正其成肌功能障碍,即恢复ISD所致SUI患者成肌细胞作用或功能。最直接的方法就是采用成肌干细胞移植进行细胞治疗。细胞治疗的目的是旨在利用多潜能干细胞的再生能力和可塑性以恢复丢失或患病的组织,替代、修复或增强受损组织或器官的生物学功能。由于肌肉干细胞来源容易,以肌肉干细胞为基础的治疗研究得到广泛开展,包括骨骼肌损伤、心肌和平滑肌损伤等,已有成功用于临床的研究报道。目前一些研究报道骨骼肌成肌细胞尿道内注射移植后能在尿道括约肌长期存活并可改善尿控功能。但是成肌细胞移植存在许多问题,包括移植后细胞存活率低下以及增殖能力不强,这些均限制了卫星细胞移植治疗的应用。MDSCs是肌肉内高度未分化的多潜能干细胞,具有增殖快、融合慢、多分化潜能等特性,移植后存活率高等特点,是一种理想的细胞移植物。由于MDSCs数量极少,因此MDSCs的分离和体外培养是MDSCs移植的关键,目前尚无MDSCs体外培养研究报道。MDSCs在体外和体内均具有多分化潜能,其分化和生存均受微环境的影响,实验所采用的动物、模型的建立方法以及细胞的注射时机等均更多还原

【Abstract】 Intrinsic sphincter deficiency(ISD) is the most common cause of stress urinary incontinence(SUI), especially in old women. There are still no long-term effective treatment for SUI due to ISD so far. Since patients with ISD have myogenic-dominant damages with urethral sphincter, stem cell transplantation may be a better way for repairing muscle injury so as to correct the defects in structure and function of sphincter urethral muscle thoroughly.Muscle derived-stem cell(MDSC), a highly undifferentiated multipotential cell, is characterized by rapid proliferation, slow fusing and multipotential differentiation. Its survival rate is significantly higher than that of satellite cells after transplantation. So it may be an ideal cell used for therapy of SUI with better alloimmunity regulation ability. Previous study showed that MDSCs injected into bladder smooth muscle layer and urethra survived and formed myofibrils. Till now, animal model which can authentically mimic human SUI has not been established. While differentiation of MDSCs is closely related to its microenvironment. In this study, MDSCs were isolated and cultured in vitro, and were transplanted into proximal urethra of rats with SUI, and the differentiation of MDSCs and metergasis of periurethral intrinsic sphincter after transplantation were systematically examined. We found that transplated MDSCs survived and differentiated into myofibers, and the function of urethral sphincter was improved. The results provide reliable theoretical basis for muscle stem cell transplantation in SUI therapy. Materials and methods1 Materials1.1 Experimental AnimalsThe experiments were performed on normal female Sprague-Dawley rats (3-4 weeks old and new born rats) purchased from Experimental Animal Center ,Research Institute of Filed Surgery, Third Military Medical University.1.2 Strains and reagents:更多还原