A New Model for In Vivo Vestibular Pharmacology

体内前庭药理学的新模型

• 批准号: 7991387
• 负责人: LARRY F HOFFMAN
• 金额: $ 23.1万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-08-01 至 2012-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7991387
• 关键词: 6-Cyano-7-nitroquinoxaline-2,3-dione; AMPA Receptors; Acute; Address; Affect; Afferent Neurons; Agonist; Anterior semicircular canal (body structure); Beds; Biological Models; Biomedical Research; Characteristics; Chinchilla (genus); Chronic; Code; Collaborations; Crista ampullaris; Data; Dendrites; Development; Endocytosis; Engineering; Epithelium; Experimental Models; Exploratory/Developmental Grant; Funding; Future; Gentamicins; Hair Cells; Head Movements; Image; Individual; Investigation; Kainic Acid; Kinetics; Labyrinth; Lead; Lesion; Liquid substance; Mechanics; Microfluidic Microchips; Microfluidics; Modeling; Monitor; Morphologic artifacts; Neuraxis; Neurobiology; Output; Perfusion; Perilymph; Peripheral; Pharmacologic Substance; Pharmacology; Pilot Projects; Plants; Preparation; Process; Rehabilitation therapy; Research; Role; Sampling; Semicircular canal structure; Sensory; Sensory Process; Signal Transduction; Solutions; Specific qualifier value; Stimulus; Sulfonamides; System; Temperature; Testing; Tissues; Utricle structure; Vestibular Hair Cells; cadmium ion; design; efficacy testing; genetic regulatory protein; in vivo; in vivo Model; inner ear diseases; neurochemistry; neuroepithelium; neuroregulation; neurotransmission; novel; pressure; public health relevance; receptor; relating to nervous system; research study; response; tool

DESCRIPTION (provided by applicant): This application represents an exploratory and development proposal to design, test, and fabricate an experimental model in which acute perfusions of the inner ear labyrinth can be achieved for investigations of vestibular pharmacology. The principal advantage of this new model is that the pharmacologic manipulations can be introduced directly into the labyrinth while recording the discharge of primary afferent neurons, representing the output of vestibular sensory epithelia. Therefore, the effect of the manipulations on spontaneous and stimulus-evoked discharge can be directly determined, enabling future investigations addressing a wide variety of questions for which contemporary pharmacologic tools (e.g. receptor agonists and antagonists, conductance-specific agonists and antagonists, etc.) are applicable. Two hypotheses will be tested through a set of specific aims that will fully test the efficacy of the model. A perfusate delivery system will be constructed that addresses key technical issues, specific to the basic function of the peripheral vestibular system, in its design. Pilot studies have identified potential artifacts in afferent discharge that likely resulted from abrupt changes in perfusate pressure. The perfusate delivery system will be specifically designed and fabricated to eliminate or minimize these artifacts. The design and fabrication of this system will reflect a collaboration between neurobiology and microfluidics engineering, using tools of micro-electro- mechanical systems (MEMS) engineering to construct a microfluidics device (chip) to manage the flow of perfusate directly to the inner ear perilymphatic space of specially prepared chinchillas. A test battery of perfusate solutions will be utilized that address the accessibility of specific solution constituents to hair cells and afferent neurons projecting throughout the crista and utricular neuroepithelia. These experiments have electrophysiologic as well as morphologic components, whereby test solutions will be delivered and the effects monitored through afferent discharge recordings as well as from direct imaging of the incorporation of these solutions by vestibular hair cells. Experiments will be conducted that will test a second hypothesis regarding the presence of transmembrane AMPA-receptor regulatory proteins (TARPs) within the afferent neurons. While providing a detailed direct test of the efficacy of the preparation for pharmacologic manipulations, these experiments will also address the functionality of TARPs in vestibular afferents. These results have the potential to motivate a new line of investigation for sensory processing in the peripheral vestibular system. PUBLIC HEALTH RELEVANCE: The research to be conducted under this exploratory and development proposal will produce a mammalian model system through which direct testing of pharmaceutical agents can be conducted with respect to their influence on the inner ear vestibular system and the signals that are transmitted to the central nervous system. The results from this investigation will lead to future studies ameliorating our understanding of neurochemical and pharmacologic interactions within the inner ear. This system may also provide a test bed for new treatments of inner ear disorders, as well as contribute to the development of new therapies that will assist in neural rehabilitation of damaged inner ear tissues.

描述（由申请人提供）：本申请代表了一种探索性和开发性提案，旨在设计、测试和制造一种实验模型，在该模型中可以实现内耳迷路的急性灌注，用于前庭药理学研究。这种新模型的主要优点是，药理学操作可以直接引入到迷路，同时记录初级传入神经元的放电，代表前庭感觉上皮的输出。因此，可以直接确定操作对自发放电和刺激诱发放电的影响，使得未来的研究能够解决当代药理学工具（例如受体激动剂和拮抗剂，电导特异性激动剂和拮抗剂等）是适用的。两个假设将通过一系列具体目标进行测试，这些目标将充分测试模型的功效。灌注液输送系统将被构建，解决关键技术问题，具体到外周前庭系统的基本功能，在其设计。初步研究已经确定了传入放电中可能由灌注液压力突然变化引起的潜在伪影。灌注液输送系统将专门设计和制造，以消除或最大限度地减少这些伪影。该系统的设计和制造将反映神经生物学和微流体工程之间的合作，使用微机电系统（MEMS）工程的工具来构建微流体装置（芯片），以管理灌注液直接流向专门制备的龙猫的内耳外淋巴空间。将使用一组试验灌注液溶液，以解决特定溶液成分对毛细胞和投射到整个嵴和椭圆囊神经上皮的传入神经元的可及性。这些实验具有电生理学和形态学组成部分，由此将递送测试溶液，并且通过传入放电记录以及通过前庭毛细胞对这些溶液的掺入的直接成像来监测效果。实验将进行，将测试第二个假设，跨膜AMPA受体调节蛋白（TARPs）的传入神经元内的存在。在提供用于药理学操作的制剂的功效的详细直接测试的同时，这些实验还将解决TARP在前庭传入中的功能。这些结果有可能激发一个新的调查线的感觉处理在外周前庭系统。 公共卫生相关性：根据这一探索和开发建议进行的研究将产生一个哺乳动物模型系统，通过该系统可以直接测试药剂对内耳前庭系统的影响以及传递到中枢神经系统的信号。这项研究的结果将导致未来的研究，改善我们的理解，神经化学和药理学的相互作用在内耳。该系统还可以为内耳疾病的新治疗提供测试平台，并有助于开发有助于受损内耳组织神经康复的新疗法。