Murine slow onset outlet obstruction as a model of human voiding dysfunction

描述（由申请人提供）：老年男性表现为良性前列腺增生（BPH），可导致下尿路症状（LUTS）、流量减少、排尿延长、逼尿肌不稳定（DI）、排尿困难、尿潴留和肾积水。临床前模型通过突然收紧尿道周围的结扎线来模拟这一点，导致Dl在几周内发作;尿道收缩的即时发作可能与部分出口梗阻有重要区别，部分出口梗阻在人类中需要五十年或更长时间才能发展，在小鼠中需要数月。在开发了测量清醒小鼠中尿流和排尿持续时间的方法后，我们将注意力转向已知发展与probasin驱动的表达系统相关的尿路梗阻的几种转基因小鼠品系（TRAMP、TRAMP-FVB、MPAKT和PbPRL）。到目前为止，在两个菌株中发生了出口梗阻的典型排尿功能变化。自动图像采集证实了长时间搏动性排尿，而不是溢出性尿失禁。组织学检查证实肿瘤形成、尿道下腺增大和其他与梗阻一致的变化。MPAKT小鼠在不存在侵袭性癌症的情况下记录为在>400天时阻塞。PbPRL小鼠还阻塞与催乳素诱导的良性增生相关的。这些转基因小鼠显示出作为慢性膀胱出口梗阻的非手术模型的前景。我们将监测排尿功能障碍的发展，并使用软组织锥形束计算机断层扫描方法（锥形束CT）非侵入性测量前列腺大小。对比研究提供了检测输尿管积水，膀胱囊泡形成，膀胱壁厚度增加的发病在体内。组织学将用于确认影像学结果，并描述潜在的膀胱肥大和纤维化。用于BPH临床管理的药物的药理学挑战将在其生命周期内进行，以揭示排尿功能的功能性沉默代偿性变化，并证明排尿功能受损的治疗增强。我们希望描述三个阶段的BPH在小鼠，即无症状，功能障碍，和肾积水，并观察代偿和失代偿过程。在良性前列腺肥大和其他膀胱疾病中观察到的下尿路症状的小鼠模型的开发有望增加对潜在疾病过程的理解，并最终帮助预测疾病在个体患者中的进展。许多药物是通过研究正常动物的作用开发的，因为这种疾病的真实模型并不存在。有效的疾病动物模型应与处方药治疗的患者相似。这些模型有助于识别新型药物及其副作用的可能性。

DESCRIPTION (provided by applicant): Aging men manifest Benign Prostatic Hyperplasia (BPH) that can result in lower urinary tract symptoms (LUTS), decreased flow, prolonged voiding, detrusor instability (Dl), nocturia, retention, and hydronephrosis. Preclinical models mimic this by suddenly tightening a ligature around the urethra, resulting in onset of Dl in a few weeks; instant onset of urethral constriction is likely to differ importantly from partial outlet obstruction that takes five or more decades to develop in humans and months in mice. After developing methods to measure uroflow and void duration in the awake mouse, we turned our attention to several transgenic mouse strains (TRAMP, TRAMP-FVB, MPAKT and PbPRL) known to develop urinary obstruction associated with probasin-driven expression systems. Changes in voiding function typical of outlet obstruction have occurred in two strains to date. Automated image capture confirmed prolonged pulsatile voiding, not overflow incontinence. Histologic study confirmed neoplasia, suburethral gland enlargement, and other changes consistent with obstruction. The MPAKT mouse is documented to obstruct at >400 days in the absence of invasive cancer. The PbPRL mouse also obstructs associated with prolactin-induced benign hyperplasia. These transgenic mice show promise as nonsurgical models of slow-onset bladder outlet obstruction. We will monitor the development of voiding dysfunction, and measure prostate size noninvasively using soft tissue conebeam computed tomographic methods (conebeam CT). Contrast studies offer detection of the onset of ureterohydronephrosis, bladder vesiculation, and increased bladder wall thickness in vivo. Histopathology will be used to confirm imaging findings, and to describe potential bladder hypertrophy and fibrosis. Pharmacologic challenges with medications used for clinical management of BPH will be administered across their lifespan to reveal functionally silent compensatory changes in voiding function, and to demonstrate therapeutic enhancement of impaired voiding function. We expect to describe three stages of BPH in the mouse, i.e. asymptomatic, dysfunctional, and hydronephrotic, and to observe compensatory and decompensation processes. Development of mouse models of the lower urinary tract symptoms seen in benign prostatic hypertrophy and other bladder diseases are expected to generate increased understanding of the underlying disease process, and eventually to help predict how the disease will progress in individual patients. Many medications are developed by studying effects in normal animals, because true models of the disease do not exist. Valid animal models of disease should respond similarly to patients treated with prescription medications. Such models help identify new types of medications as well as their likelihood of side effects.