所有大鼠均按照首都医科大学附属北京友谊医院动物实验委员会批准的方案使用。
1. 手术准备、麻醉和手术技术
注意:本研究共获得40只雌性Wistar大鼠，重200-220克。在40只大鼠中，随机选择10只作为对照组，其余作为试验组。所有动物均在首都医科大学附属北京友谊医院动物设施的无菌环境中饲养。
<ol><li>通过腹腔注射戊巴比妥钠（40mg / kg）进行全身麻醉。或者，使用3%-4%异氟醚诱导麻醉并将其维持在1%-3%（吸入）。在眼睛上涂抹眼药膏以防止干燥。然后，将大鼠放在手术平台上并提供热支持。 注意:在程序开始时给予镇痛药，如丁丙诺啡，0.05 mg / kg，SC，0.1-0.2 mL。</li>
	<li>检查麻醉深度是否对脚趾捏没有反应。用剃须刀剃掉整个背部区域的皮毛。</li>
	<li>用至少 3 个周期的两阶段擦洗（如洗必泰或聚维酮碘）对手术部位进行消毒，然后使用异丙醇。用手术胶带固定四肢，并用手术剪刀在背部做一个约3厘米的正中切口。</li>
	<li>使用手术剪刀加深皮下组织的切口，并切断附着在脊柱上的肌肉。</li>
	<li>目视识别并暴露第 13根 肋骨（连接到该肋骨的椎间空间为间隔 T13\u2012L1）。用缝合线标记第 13 根肋骨。</li>
	<li>识别后，小心地切除附着在脊柱上的肌肉并暴露椎体。切除棘上韧带和棘间韧带，以准确识别脊柱。用手术剪刀和镊子暴露L4-5的水平。 注意:由于存在薄的皮下组织，可以轻松识别棘上韧带。棘上韧带切除后，棘突之间的韧带为棘间韧带。</li>
	<li>使用凯利镊子仔细解剖L4\u2012L5椎棘突和部分横向突，露出脊髓（图1）。</li>
	<li>在L4-l5水平完全暴露髓圆锥，并用虹膜切除剪刀完全横断髓圆锥。插入一些组织包装以阻止脊髓的恢复。</li>
	<li>使用4-0不可吸收缝合线关闭外层皮肤上的覆盖肌肉和皮肤。</li>
	<li>对于对照组，执行步骤 1.1-u20121.7，并保持髓圆锥完整。按照步骤1.9关闭切口。</li>
</ol>2. 动物恢复
<ol><li>在手术后的第一个小时内将大鼠保持在温控培养箱（37°C）中，并监测它们直到它们胸骨或积极移动。 注意:完全恢复大约需要半小时。</li>
	<li>将动物转移到装有足够食物和水的干净笼子中。将老鼠放在单独的笼子里。 注意:当测试组中的大鼠仅在前腿的帮助下移动时，表明横断的成功，而对照组中的大鼠可以正常行走。</li>
</ol>3. 后期运营管理
<ol><li>腹腔注射青霉素G，一种抗生素（每只动物50，000U / mL）。术后48小时每6-12小时给予丁丙诺啡，0.05mg / kg，SC，0.1-0.2mL等镇痛药。</li>
	<li>在下胃压迫膀胱以帮助排尿。每天在同一时间（上午 8 点和晚上 8 点）执行此操作两次，持续六周。 注意:逼尿肌正常收缩的丧失是DU的标志。</li>
	<li>将所有大鼠安置在代谢笼中，每只大鼠都包含一个尿液收集漏斗，放置在先前称重的吸收纸上以监测排尿和尿失禁。</li>
	<li>收集并注意吸收纸的重量变化，分别指示排尿量（VV）和残余尿量。</li>
</ol>4. 尿动力学检查
<ol><li>在手术后六周，使用尿动力学测量设备进行膀胱测量图，如下所示。<ol><li>通过将10%水合氯醛注射到腹膜腔（3mL / kg）来麻醉大鼠。</li>
		<li>压缩膀胱排尿，然后使用胶带将大鼠固定在手术平台上。</li>
		<li>将硬膜外导管（3F）插入膀胱，并通过三肢管连接尿动力学测量设备，硬膜外导管和输液泵。</li>
		<li>以0.2mL / min的速度泵送生理盐水以进行尿动力学测量（见 材料表）。记录MCC和DOP以及膀胱的顺应性（通过将膀胱体积除以逼尿肌的压力δ δ计算）。</li>
	</ol></li>
</ol>5. 统计分析
<ol><li>使用市售软件执行统计分析。</li>
	<li>使用柯尔莫哥罗夫-斯米尔诺夫检验来检验数据的正态性。</li>
	<li>将正态分布变量表示为具有标准差的平均值。使用双尾配对学生 t 检验来比较两组膀胱测量图的参数。 注: p < 0.05表示差值具有统计学意义。</li>
</ol>

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作者没有什么可透露的。

贫铀是男性和女性下尿路症状的常见原因。这是一个复杂的症状群，几乎没有治疗选择，可以显着降低受影响者的生活质量（Qol）18。尽管人们认为贫铀是多因素的，但对其发病机制的理解仍然很初步。研究表明，贫铀的发病机制可能与肌源性和神经源性因素有关。
在肌源性假说中，观察到患有贫铀的人可能比健康衰老的人经历更显着的逼尿肌收缩力下降。...

逼尿肌活动不足（DU）是一种典型的下尿路功能障碍，至今仍在研究中。尽管贫铀已由国际尿失禁协会（ICS）1定义，但使用许多不同的术语来指代这种疾病，例如"逼尿肌衰竭"、"收缩性膀胱"、"逼尿肌反射消失"2。根据国际尿失禁协会 （ICS） 在 2002 年的定义，DU 是一种力量和持续时间减少的收缩，导致膀胱排空时间延长，从而导致无法在正常时间内实现膀胱完全排空。
DU 可能影响 48% 的男性和 12% 的女性（>70 岁）3 伴有下尿路症状。它似乎是多因素的，并且没有有效的治疗方法。据悉，DU在神经源性膀胱功能障碍患者中普遍存在，如多发性硬化症4、糖尿病5、帕金森病6或脑卒中7。贫铀也可由医源性神经损伤引起，例如腹腔镜子宫切除术、前列腺切除术或其他小骨盆的手术干预8.由于缺乏合适的动物模型进行研究，贫铀的病理生理学变化和可用的治疗方法仍然令人困惑。
排尿反射由脊柱-球脊髓通路控制，该通路结合了脑桥排尿中心、骶副交感神经核和更高级的皮质中心9。排尿反射的激活和维持主要取决于感觉信号从膀胱到更高级的皮层中心的定期传输。可以推测感觉功能障碍会导致 DU。
大多数与下尿路功能障碍相关的实验动物研究都集中在膀胱过度活动症（OAB）模型10上。这些模型提供了对OAB病理生理学和预后的合理理解。然而，只有少数 DU 模型被报道，例如脊髓上损伤（局部病变、去脑和大脑中动脉闭塞）、脊髓横断或挫伤、全身性（例如环磷酰胺）或膀胱内给予刺激性或炎症性物质（例如酸、丙烯醛和脂多糖）11，12，13，14.在这些方法中，只有脊髓横断或挫伤法可用于建立DU13的动物模型。由于严重的创伤，涉及脑桥排尿中心和高级皮层中心损伤的尝试被放弃。因此，人们越来越注意在排尿反射中心找到一个准确的位置，以最小的副作用诱导贫铀。
如前所述，诱导贫铀的机制之一是损伤脊髓以损害排尿反射的信号通路。艾伦的减重方法是为了建立脊髓受伤的实验动物而开发的15。但是，没有关于该方法的进一步实验数据。此外，由于部分动物在没有DU的情况下恢复了中风后的脊柱功能，因此不能将其视为生成DU动物模型16的完美方法。
1987年，布雷格曼发现了一种横断脊髓的过程，以生成DU动物模型，并获得了实验数据17。然而，该方法并未应用于建立贫铀动物模型。当时，研究人员仍然对DU的发病机制感到困惑。由于脊髓中与OAB或DU诱导相关的位置彼此相邻，因此他们无法找到脊髓损伤的准确位置以诱导DU17。OAB和DU要么一起引入，要么通过这种方法单独引入。因此，这种方法虽然引入了DU，但它并不精确，不能用于理解DU的发生和处理。
如上所述，缺乏合适的贫铀动物模型是贫铀研究的主要障碍之一。 研究人员一直在寻找一种准确且可管理的模型，可以模拟贫铀的病理学。在过去20年中，即使是贫铀的治疗方案也没有显著改善。总的来说，非常需要描述建立DU动物模型的标准协议。
因此，在本文中，我们描述了一种通过圆锥髓质横断成功建立DU大鼠模型的方法。在L4-L5水平进行横断，以分离髓圆锥。记录并分析膀胱的最大膀胱容量（MCC），逼尿肌开口压力（DOP）和膀胱顺应性以验证方案。下面所述的协议以标准化的方式结合了可行性和可靠性，以建立贫铀动物模型，模拟贫铀的发生和处理。该协议可用作进一步研究DU的技术。

<table><tbody><tr><td>0.9% saline</td><td>Wuhan Prosai Company</td><td>EY-C1178</td><td>pump for urodynamic measurement</td></tr><tr><td>10% chloral hydrate</td><td>Shandong Yulong Co., Ltd</td><td>H37022673</td><td>3mL/kg, administered intraperitoneally</td></tr><tr><td>Buprenorphine Hydrochloride Injection</td><td>Tianjin Pharmaceutical Research Institute Pharmaceutical Co. LTD</td><td>H12020275</td><td>0.05mg/kg subcutaneously 24h and 48h postoperation</td></tr><tr><td>Epidural Catheter</td><td>Shandong Xinghua Co, Ltd</td><td>VABR3L</td><td>for urodynamic measurement</td></tr><tr><td>Penicillin G</td><td>Alta Technology Co., Ltd</td><td>1ST5637</td><td>50,000 unit/ml per animal</td></tr><tr><td>pentobarbital</td><td>Beijing solabo Technology Co., Ltd</td><td>NK-WF0001</td><td>40 mg/kg, administered intraperitoneally</td></tr><tr><td>Suture line(4-0)</td><td>ETHICON</td><td>VCP422H</td><td>suture the injury</td></tr><tr><td>Three-limb tube</td><td>Shandong Xinghua Co, Ltd</td><td>VAB3T</td><td>for urodynamic measurement</td></tr><tr><td>Trace infusion pump</td><td>Zhejiang Smith Medical Instrument Co., Ltd</td><td>20162540335</td><td>Pump the saline at a speed of 0.2ml/min for urodynamic measurement</td></tr><tr><td>Urodynamic measurement equipment</td><td>Medical Measurement SystemsB.V.</td><td>08-0467</td><td>urodynamic measurement equipment can not only help the diagnosis of dysuria, but also provide objective materials for treatment and therapeutic effect. It is the most commonly used examination method in clinical diagnosis and treatment of lower urinary tract functional diseases</td></tr><tr><td>Wistar Rats</td><td>HFK Biotechnology Co.Ltd,Beijing ,China</td><td>SCXK2012-0023</td><td>200-220g</td></tr></tbody></table>

detrusor underactivity model in rats by conus medullaris transection

所提出的协议的目标是通过圆锥髓质横断在大鼠中建立逼尿肌活动不足（DU）模型。在总共40只雌性Wistar大鼠（对照组:10只大鼠;试验组:30只大鼠）中，体重200-220 g，在试验组中，髓圆锥在L4\u2012L5水平进行横断。将所有大鼠在相同的环境条件下饲养和喂养六周。在测试组中，每天进行两次排尿，持续六周，并记录平均残余尿量。两组均行膀胱测量图。记录并计算膀胱的最大膀胱测量容量（MCC），逼尿肌开放压力（DOP）和膀胱顺应性。测试组在手术后，无论是在脊柱休克期间还是之后，都显示出明显的尿潴留。但对照组未见异常。与对照组相比，试验组的MCC和膀胱顺应性显著高于试验组（3.24 ± 2.261 mL vs 1.04 ± 0.571 mL;0.43 ± 0.578 mL/cmH 2 O 对比 0.032 ± 0.016 mL/cmH 2 O），而试验组的DOP低于对照组（20.28 ± 14.022 cmH 2 O与35 ± 13.258 cmH22这种通过圆锥髓质横断建立贫铀动物模型的方法为更好地了解DU的病理生理学提供了绝佳的机会。

圆锥髓质横断的整个过程可以由经验丰富的外科医生在45分钟内完成。我们的实验室已经进行了100多例髓圆锥横断手术。成功率超过95%，由大鼠的存活率和成功诱导DU定义。尿动力学试验证实了DU的诱导。
根据我们的经验，贫铀的诱导可以通过残余尿量初步评估。手术后立即观察到尿液潴留。试验组术后第2天出现容量峰值点，体积下降逐渐持续10 d左右。手术后十天，体积达到...

Watch this Scientific Journal Video about Detrusor Underactivity Model in Rats by Conus Medullaris Transection at JoVE.com

Detrusor Underactivity Model in Rats by Conus Medullaris Transection

我们提出了一种通过大鼠髓圆锥横断建立逼尿肌活动不足模型的方法。在这些动物中成功刺激了逼尿肌活动不足。该模型可用于研究尿路功能。

大鼠逼尿肌活动不足模型通过圆锥髓质横断

The goal of the presented protocol was to establish a detrusor underactivity (DU) model in the rat through conus medullaris transection. Laminectomy was ...

detrusor-underactivity-model-in-rats-by-conus-medullaris-transection

Universidad de Cartagena UDEC

Research

JoVE Journal

Neuroscience

2.0K 次观看.  Capital Medical University. 我们提出了一种通过大鼠髓圆锥横断建立逼尿肌活动不足模型的方法。在这些动物中成功刺激了逼尿肌活动不足。该模型可用于研究尿路功能。

视频: Detrusor Underactivity Model in Rats by Conus Medullaris Transection

Evaluation of Biomaterials for Bladder Augmentation using Cystometric Analyses in Various Rodent Models

Renal function and continence of urine are critically dependent on the proper function of the urinary bladder, which stores urine at low pressure and expels it with a precisely orchestrated contraction. A number of congenital and acquired urological anomalies including posterior urethral valves, benign prostatic hyperplasia, and neurogenic bladder secondary to spina bifida/spinal cord injury can result in pathologic tissue remodeling leading to impaired compliance and reduced capacity1. Functional or anatomical obstruction of the urinary tract is frequently associated with these conditions, and can lead to urinary incontinence and kidney damage from increased storage and voiding pressures2. Surgical implantation of gastrointestinal segments to expand organ capacity and reduce intravesical pressures represents the primary surgical treatment option for these disorders when medical management fails3. However, this approach is hampered by the limitation of available donor tissue, and is associated with significant complications including chronic urinary tract infection, metabolic perturbation, urinary stone formation, and secondary malignancy4,5.
Current research in bladder tissue engineering is heavily focused on identifying biomaterial configurations which can support regeneration of tissues at defect sites. Conventional 3-D scaffolds derived from natural and synthetic polymers such as small intestinal submucosa and poly-glycolic acid have shown some short-term success in supporting urothelial and smooth muscle regeneration as well as facilitating increased organ storage capacity in both animal models and in the clinic6,7. However, deficiencies in scaffold mechanical integrity and biocompatibility often result in deleterious fibrosis8, graft contracture9, and calcification10, thus increasing the risk of implant failure and need for secondary surgical procedures. In addition, restoration of normal voiding characteristics utilizing standard biomaterial constructs for augmentation cystoplasty has yet to be achieved, and therefore research and development of novel matrices which can fulfill this role is needed.
In order to successfully develop and evaluate optimal biomaterials for clinical bladder augmentation, efficacy research must first be performed in standardized animal models using detailed surgical methods and functional outcome assessments. We have previously reported the use of a bladder augmentation model in mice to determine the potential of silk fibroin-based scaffolds to mediate tissue regeneration and functional voiding characteristics.11,12 Cystometric analyses of this model have shown that variations in structural and mechanical implant properties can influence the resulting urodynamic features of the tissue engineered bladders11,12. Positive correlations between the degree of matrix-mediated tissue regeneration determined histologically and functional compliance and capacity evaluated by cystometry were demonstrated in this model11,12. These results therefore suggest that functional evaluations of biomaterial configurations in rodent bladder augmentation systems may be a useful format for assessing scaffold properties and establishing in vivo feasibility prior to large animal studies and clinical deployment. In the current study, we will present various surgical stages of bladder augmentation in both mice and rats using silk scaffolds and demonstrate techniques for awake and anesthetized cystometry.

Surgical stages of bladder augmentation are described using 3-D scaffolds in murine and rat models. To test the efficacy of biomaterial configurations for use in bladder augmentation, techniques for both awake and anesthetized cystometry are presented.

膀胱膀胱分析各种啮齿类动物模型中使用的增广的生物材料评价

Renal function and continence of urine are critically dependent on the proper function of the urinary bladder, which stores urine at low pressure and ...

科研

生物工程

The Use of Cystometry in Small Rodents: A Study of Bladder Chemosensation

The lower urinary tract (LUT) functions as a dynamic reservoir that is able to store urine and to efficiently expel it at a convenient time. While storing urine, however, the bladder is exposed for prolonged periods to waste products. By acting as a tight barrier, the epithelial lining of the LUT, the urothelium, avoids re-absorption of harmful substances. Moreover, noxious chemicals stimulate the bladder's nociceptive innervation and initiate voiding contractions that expel the bladder's contents. Interestingly, the bladder's sensitivity to noxious chemicals has been used successfully in clinical practice, by intravesically infusing the TRPV1 agonist capsaicin to treat neurogenic bladder overactivity1. This underscores the advantage of viewing the bladder as a chemosensory organ and prompts for further clinical research. However, ethical issues severely limit the possibilities to perform, in human subjects, the invasive measurements that are necessary to unravel the molecular bases of LUT clinical pharmacology. A way to overcome this limitation is the use of several animal models2. Here we describe the implementation of cystometry in mice and rats, a technique that allows measuring the intravesical pressure in conditions of controlled bladder perfusion.
	After laparotomy, a catheter is implanted in the bladder dome and tunneled subcutaneously to the interscapular region. Then the bladder can be filled at a controlled rate, while the urethra is left free for micturition. During the repetitive cycles of filling and voiding, intravesical pressure can be measured via the implanted catheter. As such, the pressure changes can be quantified and analyzed. Moreover, simultaneous measurement of the voided volume allows distinguishing voiding contractions from non-voiding contractions3.
	Importantly, due to the differences in micturition control between rodents and humans, cystometric measurements in these animals have only limited translational value4. Nevertheless, they are quite instrumental in the study of bladder pathophysiology and pharmacology in experimental pre-clinical settings. Recent research using this technique has revealed the key role of novel molecular players in the mechano- and chemo-sensory properties of the bladder.

Cystometry is an efficient technique to measure bladder function of small animals in vivo. The bladder is continuously infused at rates controlled through an intravesical catheter, whereas the urethra is left free for micturition. This allows for repetitive filling and emptying of the bladder, while intravesical pressure and voided volume are recorded.

的的膀胱测压小老鼠：A膀胱Chemosensation研究的使用

	The lower urinary tract (LUT) functions as a  dynamic reservoir that is able to store urine and to efficiently expel it at a  convenient time. While ...

医学

Urinary Bladder Distention Evoked Visceromotor Responses as a Model for Bladder Pain in Mice

Approximately 3-8 million people in the United States suffer from interstitial cystitis/bladder pain syndrome (IC/BPS), a debilitating condition characterized by increased urgency and frequency of urination, as well as nocturia and general pelvic pain, especially upon bladder filling or voiding. Despite years of research, the cause of IC/BPS remains elusive and treatment strategies are unable to provide complete relief to patients. In order to study nervous system contributions to the condition, many animal models have been developed to mimic the pain and symptoms associated with IC/BPS. One such murine model is urinary bladder distension (UBD). In this model, compressed air of a specific pressure is delivered to the bladder of a lightly anesthetized animal over a set period of time. Throughout the procedure, wires in the superior oblique abdominal muscles record electrical activity from the muscle. This activity is known as the visceromotor response (VMR) and is a reliable and reproducible measure of nociception. Here, we describe the steps necessary to perform this technique in mice including surgical manipulations, physiological recording, and data analysis. With the use of this model, the coordination between primary sensory neurons, spinal cord secondary afferents, and higher central nervous system areas involved in bladder pain can be unraveled. This basic science knowledge can then be clinically translated to treat patients suffering from IC/BPS.

Approximately 3-8 million people in the United States suffer from interstitial cystitis/bladder pain syndrome (IC/BPS), a debilitating condition characterized in part by pelvic pain. In order to study nervous system contributions to the condition, a physiological model of urinary bladder pain is used in mice and rats.

膀胱胀诱发内脏运动反应为膀胱疼痛小鼠模型

Approximately 3-8 million people in the United States suffer from interstitial cystitis/bladder pain syndrome (IC/BPS), a debilitating condition ...

Bladder Smooth Muscle Strip Contractility as a Method to Evaluate Lower Urinary Tract Pharmacology

We describe an in vitro method to measure bladder smooth muscle contractility, and its use for investigating physiological and pharmacological properties of the smooth muscle as well as changes induced by pathology. This method provides critical information for understanding bladder function while overcoming major methodological difficulties encountered in in vivo experiments, such as surgical and pharmacological manipulations that affect stability and survival of the preparations, the use of human tissue, and/or the use of expensive chemicals. It also provides a way to investigate the properties of each bladder component (i.e. smooth muscle, mucosa, nerves) in healthy and pathological conditions.
The urinary bladder is removed from an anesthetized animal, placed in Krebs solution and cut into strips. Strips are placed into a chamber filled with warm Krebs solution. One end is attached to an isometric tension transducer to measure contraction force, the other end is attached to a fixed rod. Tissue is stimulated by directly adding compounds to the bath or by electric field stimulation electrodes that activate nerves, similar to triggering bladder contractions in vivo. We demonstrate the use of this method to evaluate spontaneous smooth muscle contractility during development and after an experimental spinal cord injury, the nature of neurotransmission (transmitters and receptors involved), factors involved in modulation of smooth muscle activity, the role of individual bladder components, and species and organ differences in response to pharmacological agents. Additionally, it could be used for investigating intracellular pathways involved in contraction and/or relaxation of the smooth muscle, drug structure-activity relationships and evaluation of transmitter release.
The in vitro smooth muscle contractility method has been used extensively for over 50 years, and has provided data that significantly contributed to our understanding of bladder function as well as to pharmaceutical development of compounds currently used clinically for bladder management.

This manuscript presents a simple, yet powerful, in vitro method for evaluating smooth muscle contractility in response to pharmacological agents or nerve stimulation. Main applications are drug screening and understanding tissue physiology, pharmacology,&#160;and pathology.

膀胱平滑肌收缩带作为一种方法来评估下尿路药理学

We describe an in vitro method to measure bladder smooth muscle contractility, and its use for investigating physiological and pharmacological properties ...

Nerve-sparing Mid-urethral Obstruction (NeMO) in Female Small Rodents

Partial bladder outlet obstruction (pBOO) has a high prevalence, causes significant patient burden, and immense health care costs. The most common animal model to investigate bladder remodeling in pBOO are female rodents undergoing partial obstruction at the proximal urethra. Variability in the degree of obstruction and animal mortality are major concerns with proximal obstruction. Furthermore, dissecting around the proximal urethra and bladder neck jeopardizes bladder innervation.
We developed a nerve-sparing mid-urethral obstruction (NeMO) model for pBOO avoiding the disadvantages of the traditional model. We approached the urethra just inferior to the pubic symphysis, which obviated the need for laparotomy as well as for dissection in this area; also, the striated urethral sphincter remained untouched. We performed NeMO in female Sprague-Dawley rats (12 obstructions, 6 sham animals) as well as in female C57/bl6 mice (20 obstructions, 18 sham animals). After two weeks, we evaluated bladder function, bladder mass, and body mass.
We had no mortalities among obstructed- or sham-operated female rats; as described for the traditional proximal pBOO-method, we tied the suture around the proximal urethra and a temporarily placed 0.9 mm metal rod. NeMO induced an 85% increase in bladder mass after two weeks, average residual urine volume was 0.4 mL in partially obstructed rats while only 0.03 mL in sham animals. In mice, we tested 3 sizes of cannulas that we placed along the urethra when tying the suture. We found that using a 27-gauge cannula resulted in over 50% animal mortality; placing the 25-gauge cannula did not yield the desired response in increasing bladder mass; utilizing a 26-gauge cannula yielded favorable results with minimal animal mortality (1/8) yet a significant 2-fold increase in bladder mass.

Nerve-sparing Mid-urethral Obstruction NeMO in Female Small Rodents

Traditional modeling of partial bladder outlet obstruction in rodents is fraught with animal mortality. A denervation injury from dissection around the proximal urethra and bladder neck is also of major concern. We developed and evaluated a safe and reliable mid-urethral obstruction model, avoiding the shortcomings of the traditional model.

在女小鼠害保留神经的中期尿道梗阻（NEMO）

Partial bladder outlet obstruction (pBOO) has a high prevalence, causes significant patient burden, and immense health care costs. The most common animal ...

Evaluating the Procedure for Performing Awake Cystometry in a Mouse Model

Awake filling cystometry has been used for a long time to evaluate bladder function in freely moving mice, however, the specific methods used, vary among laboratories. The goal of this study was to describe the microsurgical procedure used to implant an intravesical tube and the experimental technique for recording urinary bladder pressure in an awake, freely moving mouse. In addition, experimental data is presented to show how surgery, as well as tubing type and size, affect lower urinary tract function and recording sensitivity. The effect of tube diameter on pressure recording was assessed in both polyethylene and polyurethane tubing with different internal diameters. Subsequently, the best performing tube from both materials was surgically implanted into the dome of the urinary bladder of male C57BL/6 mice. Twelve-hour, overnight micturition frequency was recorded in healthy, intact animals and animals 2, 3, 5, and 7 days post-surgery. At harvest, bladders were assessed for signs of swelling using gross observation and were subsequently processed for pathological analysis. The greatest extent of bladder swelling was observed on day 2 and 3, which correlated with behavioral voiding data showing significantly impaired bladder function. By day 5, bladder histology and voiding frequency had normalized. Based on the literature and evidence provided by our studies, we propose the following steps for in vivo recording of intravesical pressure and voided volume in an awake mouse: 1) Perform the surgery using an operating microscope and microsurgical tools, 2) Use polyethylene-10 tubing to minimize movement artifacts, and 3) Perform cystometry on post-operative day 5, when bladder swelling resolves.

This study describes the surgical procedures and experimental techniques for performing awake cystometry in a freely moving mouse. In addition, it provides experimental evidence to support its optimization and standardization.

评估在鼠标模型中执行唤醒膀胱测压的过程

Awake filling cystometry has been used for a long time to evaluate bladder function in freely moving mice, however, the specific methods used, vary among ...

A Decentralized (Ex Vivo) Murine Bladder Model with the Detrusor Muscle Removed for Direct Access to the Suburothelium during Bladder Filling

Previous studies have established the release of chemical substances from flat bladder mucosa sheets affixed in Ussing chambers and exposed to changes in hydrostatic pressure or mechanical stretch and from cultured urothelial cells upon hydrostatic pressure changes, stretch, cell swelling, or drag forces, and in bladder lumen at end of filling. Such findings led to the assumption that these mediators are also released in suburothelium (SubU)/lamina propria (LP) during bladder filling, where they affect cells deep in the bladder wall to ultimately regulate bladder excitability. There are at least two obvious limitations in such studies: 1) none of these approaches provide direct information about the presence of mediators in SubU/LP, and 2) the stimuli used are not physiological and do not recapitulate authentic filling of the bladder. Here, we discuss a procedure that enables direct access to the suburothelial surface of the bladder mucosa in the course of bladder filling. The murine detrusor-free preparation we created closely resembles filling of the intact bladder and allows pressure-volume studies to be performed on the bladder in the absence of confounding signaling from spinal reflexes and detrusor smooth muscle. Using the novel detrusor-free bladder model, we recently demonstrated that intravesical measurements of mediators cannot be used as a proxy to what has been released or present in the SubU/LP during bladder filling. The model enables examination of urothelium-derived signaling molecules that are released, generated by metabolism and/or transported into the SubU/LP during the course of bladder filling to transmit information to neurons and smooth muscle of the bladder and regulate its excitability during continence and micturition.

A Decentralized Ex Vivo Murine Bladder Model with the Detrusor Muscle Removed for Direct Access to the Suburothelium during Bladder Filling

The detrusor-free bladder model enables direct access to the suburothelium to study local mechanisms for regulation of biologically active mediator availability in suburothelium/lamina propria during storage and voiding of urine. The preparation closely resembles filling of an intact bladder and allows pressure-volume studies to be performed without systemic influences.

分散（Ex Vivo）的毛骨球模型，去除了除位肌肉，用于在膀胱填充期间直接进入苏布罗氦

Previous studies have established the release of chemical substances from flat bladder mucosa sheets affixed in Ussing chambers and exposed to changes in ...

Cystometric and External Urethral Sphincter Measurements in Awake Rats with Implanted Catheter and Electrodes Allowing for Repeated Measurements

Lower urinary tract function is mainly assessed by means of cystometric bladder function analysis in rodents. Conventional cystometries are usually performed as terminal analysis under urethane anesthesia. It is well known that anesthetic drugs can influence bladder function. Hence, the aim of this technique is to perform cystometric measurements of the urinary bladder and external urethral sphincter in lightly restrained awake rats. For this purpose, a bladder catheter is implanted into the bladder dome. Subsequently, two electrodes are implanted bilateral to the external urethral sphincter and a ground electrode is sutured to a non-responsive skeletal muscle. The bladder catheter and the three electrodes are finally tunneled subcutaneously to the neck region and affixed to a harness. With this technique, the lower urinary tract can be measured at multiple time points in the same animal to assess lower urinary tract function. The main application of this technique is the follow-up of simultaneous urinary bladder and external urethral sphincter function in awake healthy rats and after induction of a disease or injury. Moreover, subsequent lower urinary tract monitoring can be performed during evaluation of the disease/injury and to monitor treatment efficacy.

This protocol first describes the surgical procedure of the permanent implantation of a urinary bladder catheter combined with external urethral sphincter electrodes, and second, the measurement of the function of the urinary bladder and external urethral sphincter in implanted awake animals.

压和外尿道括约肌测量在清醒大鼠植入导管和电极允许重复测量

Lower urinary tract function is mainly assessed by means of cystometric bladder function analysis in rodents. Conventional cystometries are usually ...

生物学

Urethral Stricture Induction Followed by Buccal Mucosa Graft Urethroplasty in a Rat Model

Urethral reconstruction is an important area of expertise for urologists. The buccal mucosa is considered the best option when urethral grafting is necessary, although in some cases, it is inappropriate or needs to be optimized to repair a given stricture. Therefore, developing innovative procedures and evaluating their putative success in experimental models is crucial to fit the clinical need. With this goal, this study describes a protocol in which urethral stricture was induced by electrocautery in Wistar rats. Urethral reconstruction was performed 1 week later with a buccal mucosa graft, harvested from the lower lip, and placed in a ventral onlay fashion. A retrograde urethrogram showed a significant improvement in urethral diameter after urethroplasty compared to the respective value after stricture induction. Additionally, the graft placement was assessed by blood perfusion analysis using laser Doppler. As expected, a dark blue area corresponded to the non-vascularized buccal mucosa graft. This procedure can successfully simulate the normal pathophysiological process of urethral injury and tissue modulation, as well as urethral reconstruction using a buccal mucosa graft in a reproducible manner, and serve as the basis for future research based on tissue engineering or urethral grafts.

In the present protocol, a urethral stricture induction was developed in Wistar rats, followed by urethral reconstruction with a buccal mucosa graft. A retrograde urethrogram and laser Doppler assessment were performed, validating urethral reconstruction (after stricture formation) and graft placement.

大鼠模型中的尿道狭窄诱导后进行颊粘膜移植尿道成形术

Urethral reconstruction is an important area of expertise for urologists. The buccal mucosa is considered the best option when urethral grafting is ...

Efficient Rat Model for Urethral Stricture: Electric Knife Method

Iatrogenic Injury Recapitulated: Electroexcision Technique for Urethral Stricture Modeling in Rats

Urethral stricture (US) is a common clinical condition in urology, characterized by high prevalence and morbidity across all ages. Current treatments for US, such as urethral dilatation and internal urethrotomy, fail to fully resolve the condition and are associated with high rates of recurrence and complications. 
Additionally, the pathogenesis of US is not well understood. To explore the pathogenesis of US and develop new therapeutic strategies, it is crucial to establish a standardized rat model that accurately reflects the clinical manifestations. This study outlines a straightforward and repeatable method for inducing US in rats using a high-frequency electric knife. The method involves making a longitudinal incision with the electric knife set to a unipolar mixed cutting mode at 4 W, which inflicts significant urethral damage. Histopathological analysis shows thickening of the urothelium, inflammatory infiltration, and disorganized collagen fibers. This model effectively replicates iatrogenic injury through electroexcision in the rat urethra. In summary, this study successfully establishes a new, efficient, and stable rat model of US that closely mimics the clinical scenario, providing a valuable tool for further research into the mechanisms and novel treatments for US.

In this study, we present a novel, efficient, and stable rat model of urethral stricture created through electroexcision of the rat urethra, which effectively simulates iatrogenic injury observed in clinical settings.

Urethral stricture (US) is a common clinical condition in urology, characterized by high prevalence and morbidity across all ages. Current treatments for ...