CIRCUITRY OF THE MIDGET AND PARASOL RECEPTIVE FIELD

侏儒和阳伞接受区的电路

• 批准号: 8357582
• 负责人: DENNIS MICHAEL DACEY
• 金额: $ 15.51万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-05-01 至 2012-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8357582
• 关键词: Carbenoxolone; Cells; Cobalt; Code; Color; Drug usage; Funding; Gap Junctions; Goals; Grant; Measures; National Center for Research Resources; Primates; Principal Investigator; Protocols documentation; Research; Research Infrastructure; Resources; Retinal; Retinal Cone; Series; Signal Transduction; Source; Stimulus; Synapses; Time; United States National Institutes of Health; Weight; cell type; cost; ganglion cell; presynaptic; receptive field; research study; transmission process

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The goal of this project is determine how the receptive field surround is established at the level of the ganglion cell and how the surround contributes to color-coding by identifying the cone inputs to the surround. The presynaptic hypothesis predicts that the creation of the cone bipolar center-surround organization is the critical locus for cone opponency. We showed for the first time in a mammalian retina that cone bipolar cells have robust center-surround organization comparable to their ganglion cell counterparts. We then undertook a series of experiments to attempt to selectively block ganglion cell surrounds. We found, in parasol cells, that either cobalt or the gap-junction blocker, carbenoxolone, selectively reduces surround antagonism. We are now using these drugs to assess the receptive field surround contribution to color-opponency in a number of ganglion cell classes. In a second series of experiments, we developed a new stimulus protocol to measure the strength and sign of L, M and S-cone inputs to the receptive field surrounds of midget and parasol ganglion cell types. The specific goal was to assess how cone signal weighting may be altered during transmission from outer to inner retinal circuitry. We showed that there are no gain changes from the horizontal-bipolar cell level to the ganglion cell surround and concluded that cone type-specific changes in synaptic gain are not a likely mechanism for generating color-opponent signals.

该副本是利用资源的众多研究子项目之一 由NIH/NCRR资助的中心赠款提供。对该子弹的主要支持 而且，副投影的主要研究员可能是其他来源提供的 包括其他NIH来源。 列出的总费用可能 代表subproject使用的中心基础架构的估计量， NCRR赠款不直接向子弹或副本人员提供的直接资金。 该项目的目的是确定如何在神经节电池的水平上建立接收场周围，以及周围如何通过识别向周围的锥体输入来促进颜色编码。突触前的假设预测，锥双极中心旋转组织的创建是锥体反对的关键基因座。我们在哺乳动物的视网膜中首次展示了锥双极细胞具有与神经节细胞对应物相当的稳健中心旋转组织。然后，我们进行了一系列实验，以选择性地阻断神经节细胞的周围。我们在阳伞细胞中发现，钴或间隙 - 结块剂Carbenoxolone有选择地减少拮抗作用。现在，我们正在使用这些药物来评估许多神经节细胞类别中的颜色 - 持久性的贡献。 在第二个实验中，我们开发了一种新的刺激方案，以测量L，M和S-con孔输入的强度和符号，以对Midget和Parasol Ganglion细胞类型的接收场周围环绕。 具体目标是评估从外部视网膜到内部视网膜电路传输期间如何改变锥信号加权。我们表明，从水平双极细胞水平到神经节细胞周围没有增益变化，并得出结论，突触增益的锥类型特异性变化并不是产生颜色 - op子信号的可能机制。