Mouse Urinary Bladder Identifying Targets to Treat Overactive Bladder

描述(由申请人提供)：膀胱过度活动(OAB)是患者及其照顾者痛苦的主要原因。这项提议的长期目标是确定 治疗OAB的新的治疗干预部位。由于膀胱逼尿肌收缩的嘌呤能成分(由ATP介导)在OAB中相对于正常的胆碱能成分增加，我们认为调控ATP释放的节前机制将为控制逼尿肌活动和排尿行为提供有效的靶点。我们将在小鼠和人类组织中使用电生理和肌肉收缩技术来解决三个特定的目标。具体目的1：通过测量神经元钙通道亚型在控制ATP和乙酰胆碱(ACh)释放中的作用，确定控制膀胱逼尿肌连接前的生理机制；B.确定牛肝菌毒素(Botx)组分(A-E)在切割神经末梢分泌装置的特定组件时的治疗效果，以及C.确定(-)-维沙米考(ACh摄取抑制剂)对嘌呤能和胆碱能组分的影响。特异性目的2：确定腺苷受体在逼尿肌神经传递中的作用。我们的初步实验表明，A1腺苷受体类似物调节逼尿肌活动。为了利用这一点，我们将定义这些受体作为神经调节器的作用，并测量上皮组分(尿路上皮/下尿路上皮)对神经传递和释放的影响。这一点至关重要，因为我们最近发现，尿路上皮腺苷衍生物抑制逼尿肌收缩，这表明了一种调节活动和症状的机制。这样的翻译发现将在人类逼尿肌中进行测试，以确认腺苷介导的抑制的位置和机制。具体目的3：利用新开发的模拟人OAB的体内排尿小鼠，研究OAB和膀胱功能障碍的小鼠模型，我们将：A.测定嘌呤/胆碱能传递比率；B.测试钙通道阻滞剂、腺苷类似物和BoTx部分的作用。这些研究将在确定临床目标和治疗路径的环境中整合小鼠和人类的研究结果。

DESCRIPTION (provided by applicant): Overactive bladder (OAB) is a major cause of distress for patients and their caregivers. The long term objective of this proposal is to identify novel therapeutic intervention sites for treating OAB. As the purinergic component of contraction of the bladder detrusor muscle (mediated by ATP) is increased in OAB relative to the normal cholinergic component, we propose that prejunctional mechanisms governing ATP release will provide impactful targets for controlling detrusor activity and voiding behavior. We will use electrophysiological and muscle contraction techniques in mouse and human tissues to address 3 Specific Aims. SPECIFIC AIM 1: Determine the pre-junctional physiological mechanisms controlling the detrusor muscle of the bladder by: A. measuring the contributions of neuronal Ca2+ channel subtypes in controlling ATP versus acetylcholine (ACh) release;. B. Defining the therapeutic effects of the bolultinum toxin (Botx) fractions (A-E) as they cleave specific components of the nerve terminal secretory apparatus, and C. Determine the effects of (-)-vesamicol (ACh uptake inhibitor) on the purinergic and cholinergic components. SPECIFIC AIM 2: Determine the actions of adenosine receptors on detrusor neurotransmission. Our preliminary experiments show that A1 adenosine receptor analogs modulate detrusor activity. To exploit this we will define the role of these receptors as neuromodulators and measure the influence of epithelial components (urothelium/suburothelium) on neurotransmission and release. This is critical as we recently found that urothelial adenosine derivatives inhibit detrusor contractions suggesting a mechanism for modulating activity and symptoms. Such translational findings will be tested in human detrusor confirming the site and mechanism of adenosine-mediated inhibition. SPECIFIC AIM 3: To study murine models of OAB and bladder dysfunction utilizing a newly developed in vivo voiding mouse that mimics human OAB, we will: A. Determine purinergic/cholinergic transmission ratios and B. Test the effects of Ca2+ channel blockers, adenosine analogs, and BoTx fractions. These studies will integrate the murine and human findings in a setting that confirms clinical targets and therapeutic pathways.