Synaptic Organization of the Auditory System

听觉系统的突触组织

• 批准号: 6838202
• 负责人: DOUGLAS L OLIVER
• 金额: $ 38.13万
• 依托单位: UNIVERSITY OF CONNECTICUT SCH OF MED/DNT
• 依托单位国家: 美国
• 财政年份: 1982
• 资助国家: 美国
• 起止时间: 1982-04-01 至 2008-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6838202
• 关键词: auditory nuclei; auditory pathways; auditory stimulus; binaural hearing; brain stem; cats; cell type; electrodes; electrophysiology; fluorescence microscopy; gamma aminobutyrate; guinea pigs; immunocytochemistry; inferior colliculus; laboratory rat; neural information processing; neural inhibition; neuroanatomy; neurons; olivary body; potassium channel; sound perception; synapses; tissue /cell culture

DESCRIPTION (provided by applicant): The inferior colliculus (IC) is a midbrain structure where virtually all ascending auditory information terminates in route to the auditory cortex. Our ultimate objective is to understand the cellular mechanisms that underlie sound processing in the IC. This research project will employ a diverse set of experimental approaches. (1) Experiments in the intact animal using physiological and neuroanatomical methods will show that the IC contains functional zones where the response properties of the neurons are directly related to the brainstem inputs. Experiments using axonal labels will show that major inhibitory inputs to the IC terminate in separate functional zones. Experiments using retrograde cell markers will show which inputs to the IC are related to neurons with different binaural and monaural response properties. (2) Experiments in the intact animal will study the outputs of the functional zones in the IC and may implicate the IC in pathways that lead to two different types of higher-level auditory processing: a binaural pathway conveying information about sound location, and a monaural pathway that conveys information about the spectral properties of complex sounds. (3) Experiments in a brain slice preparation of the IC will investigate neuron types defined by unique discharge patterns and specific potassium currents. These cell types also differ in their synaptic responses. The experiments will determine if the different synaptic responses are due to the synaptic inputs (mediated by ligand-gated postsynaptic receptors) or to the membrane properties (related to voltage-activated ion channels). Responses will be examined to synaptic inputs (evoked by stimulation of the lateral lemniscus) and to artificial synaptic inputs (that simulate the synaptic currents without activating the postsynaptic receptors). (4) Experiments in a brain slice preparation will investigate structure-function relationships at the morphological, molecular, and transmitter level. These experiments will morphologically label functional cell types and then test them for expression of ion channel subunits and transmitter content. (5) Finally, experiments in the intact animal will use intracellular recording to allow direct comparisons to the brain slice. We will learn whether the IC cell types are found in the adult animal, and how the intracellular responses are related to electrical stimulation of the lateral lemniscus and stimulation by monaural and binaural sounds.

描述（由申请人提供）：下丘（IC）是一种中脑结构，几乎所有上升的听觉信息终止于听觉皮层。我们的最终目标是了解IC中声音处理的基础的细胞机制。该研究项目将采用各种实验方法。 （1）使用生理和神经解剖学方法在完整动物中进行的实验将表明，IC包含功能区域，其中神经元的响应特性与脑干输入直接相关。使用轴突标签的实验将表明，在单独的功能区域中，IC终止的主要抑制性输入。使用逆行细胞标记的实验将显示IC的输入与具有不同双耳和单膜反应特性的神经元有关。 （2）完整动物中的实验将研究IC中功能区域的输出，并可能在途径中暗示IC，从而导致两种不同类型的高级听觉处理：一种双耳途径传达有关声音位置的信息，以及传达有关复杂声音光谱特性的单声道途径。 （3）在IC的脑切片制备中进行的实验将研究由独特的放电模式和特定钾电流定义的神经元类型。这些细胞类型的突触反应也有所不同。实验将确定不同的突触反应是由于突触输入（由配体门控的突触后受体介导的）还是膜特性（与电压激活的离子通道有关）。将检查对突触输入的反应（通过刺激外侧lemniscus引起的）和人工突触输入（该反应在不激活突触后受体的情况下模拟突触电流）。 （4）在脑切片制备中进行的实验将研究形态，分子和发射器水平的结构 - 功能关系。这些实验将在形态上标记功能细胞类型，然后测试它们以表达离子通道亚基和发射机含量。 （5）最后，完整动物的实验将使用细胞内记录，以直接比较脑切片。我们将了解成年动物中是否发现IC细胞类型，以及细胞内反应如何与单声道和双耳声音的侧面刺激和刺激的刺激有关。