Intraspinal circuits supporting synergy between the bladder and urethral sphincter in mice

支持小鼠膀胱和尿道括约肌协同作用的椎内回路

基本信息

批准号：
10458072
负责人：
SERGEI V KARNUP
金额：
$ 34.93万
依托单位：
UNIVERSITY OF PITTSBURGH AT PITTSBURGH
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-07-01 至 2025-05-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10458072
关键词：
3-Dimensional Anatomy Animals Area Ataxia Axon Bladder Brain C57BL/10 Mouse Cell Nucleus Chronic Development Electric Stimulation Electrophysiology (science)Exhibits Feedback Female Functional disorder Future Gender Generations Genetic Glutamates Goals Horns In Vitro Injections Interneurons Interruption Knowledge Label Lead Light Lower urinary tract Mammals Maps Mediating Methods Micturition Reflex Modification Motor Motor Neurons Mus Muscle Neurons Neurotransmitters Optics Pathway interactions Periodicity Persons Pharmacology Pontine structure Population Preparation Rattus Reaction Recovery Recovery of Function Recurrence Reflex action Regulation Relaxation Research Project Grants Residual state Rhodopsin Role Sex Differences Slice Sphincter Spinal Spinal Cord Spinal Cord Diseases Spinal cord injury Structure Synapses Techniques Testing Therapeutic Therapeutic Intervention Tracer Transgenic Mice Urethane Urethral sphincter Urinary Retention Urination Urine Viral biocytin cholinergic neuron clinical practice design excitatory neuron experimental study gender difference improved in vivo inhibitory neuron injury recovery insight intravesical mad itch virus male mouse model neural circuit neuronal circuitry neuroregulation novel therapeutics optogenetics postsynaptic pressure relating to nervous system response restoration sex sexual dimorphism side effect spinal pathway spinal tract synergism therapeutically effective urologic

项目摘要

Project summary Detrusor-sphincter-dyssynergia (DSD) is a major urological problem inducing inefficient voiding, increased amount of post-void residual urine and high intravesical pressure after spinal cord injury (SCI). Until recently the majority of studies on spinal mechanisms of coordination between external urethral sphincter (EUS) and the bladder (BL) were conducted in female rats, although in clinical practice DSD develops more often in males. Furthermore, sexual dimorphism in anatomy and function of the lower urinary tract (LUT) suggests differences in the spinal neural circuits of male and female. With development of genetic modifications and optogenetic techniques the mouse model of LUT dysfunction is becoming more useful than the rat. Therefore, in the proposed project “Intraspinal circuits supporting synergy between the bladder and urethral sphincter in mice” we will use transgenic mice of both sexes for electrophysiological, optogenetic, immunohistochemical, pharmacological and anatomical studies of spinal cord circuits involved in interaction between the bladder (BL) and the external urethral sphincter (EUS) in spinal intact animals and after spinal cord injury. We will test several hypotheses in in vivo and in vitro experiments. In urethane anesthetized animals of both sexes, we will determine functional differences in spinal regulation of micturition and in control and SCI mice. Male and female animals will be also used to determine hypothesized sexual dimorphism in LUT-related spinal circuits and their plasticity after chronic SCI. Using electrical stimulation of the Lumbar Spinal Coordinating Center (LSCC) which we have recently discovered in L3/L4 spinal segments, we will test whether an external command can initiate voiding. Using trans-synaptic viral labeling, we will trace neuronal populations involved in coordination between EUS and BL to determine structural and functional differences in LUT spinal networks between males and females. In spinal cord slice preparations, we will use transgenic mice expressing channel rhodopsin (ChR2) in inhibitory or excitatory neurons to study reactions of EUS motoneurons to light-evoked activity of LUT-related spinal interneurons embedded in specific spinal pathways, and will identify and characterize the inhibitory circuit which is responsible for EUS relaxation. We will define the role of the L3/L4 LSCC in activity of EUS motoneurons and EUS relaxation and its mode of interaction with L6/S1 motor neuronal pool. We will evaluate the contribution of a hypothesized recurrent inhibitory circuit in L6/S1 to the generation of EUS bursting and relaxation as well as to bladder-sphincter coordination. The long-term objectives of the research project are to increase our understanding of the pathophysiological mechanisms inducing DSD and voiding problems after SCI and to develop new and effective therapeutic interventions for the treatment of DSD in spinal cord disorders. Considering gender related differences in neural control of the LUT different approaches to DSD treatment in males and females may be recommended.

项目概要逼尿肌括约肌协同失调 (DSD) 是一个主要的泌尿外科问题，可导致排尿效率低下、尿频增加直到最近，脊髓损伤（SCI）后排尿后残余尿量和高膀胱内压。大多数研究是关于尿道外括约肌（EUS）和尿道外括约肌之间协调的脊柱机制尽管在临床实践中 DSD 在雄性大鼠中更常见，但膀胱 (BL) 是在雌性大鼠中进行的。此外，下尿路（LUT）的解剖和功能的性别二态性表明存在差异随着遗传修饰和光遗传学的发展，男性和女性的脊髓神经回路中。因此，LUT 功能障碍的小鼠模型比大鼠更有用。拟议项目“脊柱内回路支持膀胱和尿道括约肌之间的协同作用小鼠”我们将使用两种性别的转基因小鼠进行电生理学、光遗传学、免疫组织化学、参与膀胱（BL）之间相互作用的脊髓回路的药理学和解剖学研究以及脊柱完整动物和脊髓损伤后的尿道外括约肌（EUS）。我们将在聚氨酯麻醉的动物体内和体外实验中测试几个假设。无论性别，我们将确定脊柱排尿调节、控制和 SCI 方面的功能差异雄性和雌性小鼠也将用于确定 LUT 相关的性别二态性。慢性 SCI 后的脊髓回路及其可塑性使用腰椎协调的电刺激。我们最近在 L3/L4 脊柱节段发现了中心（LSCC），我们将测试外部是否存在命令可以启动排尿。使用跨突触病毒标记，我们将追踪参与排尿的神经元群。 EUS 和 BL 之间的协调以确定 LUT 脊柱网络的结构和功能差异在雄性和雌性之间的脊髓切片制备中，我们将使用表达通道的转基因小鼠。抑制性或兴奋性神经元中的视紫红质 (ChR2) 用于研究 EUS 运动神经元对光诱发的反应嵌入特定脊髓通路中的 LUT 相关脊髓中间神经元的活动，并将识别和表征负责 EUS 松弛的抑制电路我们将定义 L3/L4 的作用。 LSCC在EUS运动神经元活动和EUS松弛中的作用及其与L6/S1运动神经元的相互作用模式我们将评估 L6/S1 中开发的循环抑制电路对生成的贡献。 EUS 的破裂和放松以及膀胱括约肌的协调。该研究项目的长期目标是加深我们对 SCI 后诱发 DSD 和排尿问题的病理生理机制，并开发新的有效机制考虑性别相关的 DSD 治疗干预措施。 LUT 神经控制的差异男性和女性 DSD 治疗方法的不同可能是受到推崇的。