Synaptic mechanisms in the auditory system

描述（由申请人提供）：抑制的突触机制代表了我们对脑干中声信号处理的理解中的一些最大的空白。神经元的亚型，它们与谁相互连接，这些连接的效力，以及抑制信号的大小和形状是如何被控制的，所有这些都尚不清楚。考虑到作为药物靶点的抑制与大脑其他区域的疾病之间的关系，似乎对抑制系统的深入了解将对治疗听觉障碍具有临床意义。在本提案中，我们将果断地解决这些问题中的每一个，重点是无处不在的抑制性神经递质甘氨酸。首先，我们将利用绿色荧光蛋白（GFP）在抑制细胞亚群中表达的小鼠系的可用性来揭示听觉神经元常见亚型的功能和连通性，这些亚型很少使用直接电生理手段进行研究。其次，我们将确定控制抑制状态持续时间的机制，并关注突触间隙中递质清除的作用以及GABA/甘氨酸共传递在调节甘氨酸能衰减中的有希望的作用。最后，我们将确定甘氨酸是否刺激或抑制突触后神经元的机制。

DESCRIPTION (provided by applicant): Synaptic mechanisms of inhibition represent some of the greatest gaps in our understanding of the processing of acoustic signals in the brainstem. The subtypes of neurons, with whom they interconnect, the efficacy of those connections, and how the size and shape of the inhibitory signals are controlled, all these remain unclear. Given the relation between inhibition as a target for drugs and disease in other brain regions it seems likely that a deep knowledge of inhibitory systems will be of clinical relevance for treating auditory disorders. In this proposal, we will address decisively each one of these points, focusing on the ubiquitous inhibitory neurotransmitter glycine. First, we will take advantage of the availability of lines of mice in which green fluorescent protein (GFP) is expressed in subsets of inhibitory cells to reveal the function and connectivity of common subtypes of auditory neurons that have been rarely studied using direct electrophysiological means. Second, we will identify mechanisms that control the duration of the inhibitory state, and focus on the role of transmitter clearance from the synaptic cleft and the promising role of GABA/glycine cotransmission in regulation of glycinergic decays. Finally, we will determine what mechanisms set whether glycine excites or inhibits postsynaptic neurons.