The Mouse dc-Electroretinogram

小鼠直流视网膜电图

• 批准号: 6779919
• 负责人: NEAL S. PEACHEY
• 金额: $ 22.95万
• 依托单位: CLEVELAND CLINIC LERNER COM-CWRU
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-08-01 至 2006-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6779919
• 关键词: chloride channels; cone cell; electrophysiology; electroretinography; electrostimulus; genetically modified animals; high performance liquid chromatography; immunocytochemistry; laboratory mouse; neural degeneration; retinal pigment epithelium; rhodopsin; rod cell; transducin; visual photoreceptor; western blottings

DESCRIPTION (provided by applicant): The retinal pigment epithelium (RPE) is critically involved in many functions required for normal retinal function including the flow of nutrients and waste products between the photoreceptors and the choroidal circulation, the visual cycle, and the phagocytosis of shed outer segment disks. In addition, mutations in RPE-specific genes have been implicated in a wide range of hereditary retinal disease, and this information is being used to develop corresponding mouse models. In the present project, the focus is on the electrical responses generated by the RPE in response to activity of the neural retina. While specific aspects of RPE function may be studied using the electroretinogram (ERG) recorded using dc-coupled amplification, this has not been applied to the mouse. Moreover, fundamental questions remain regarding the origin of the different components of the dc-ERG. In Aim 1, we will study normal wild-type mice, to define the stimulus-response characteristics of the mouse dc-ERG, and the time course over which these develop. In Aim 2, we will test the hypothesis that the mouse dc-ERG is initiated primarily by rod photoreceptor activity, using KO lines for transducin and rhodopsin, and mutants in which the cone population is increased (rd7) or decreased (comas transgenic). In Aim 3, we will use Kir4.1 KO mice to test the hypothesis that this channel is involved in c-wave generation. In Aim 4, we will use cftr KO mice and adenoviral delivery of CFTR constructs to test the hypothesis that the fast oscillation is generated by CFTR activity. In Aim 5, we will use dc-ERG recordings to study the relationship between photoreceptor degeneration and changes in RPE function. First, we will examine how A2E accumulation in abcr-mutant mice alters RPE function. Next, we will test the hypothesis that functional RPE abnormalities occur at early stages using three lines of mice with similar rates of photoreceptor degeneration. In two, the primary defect resides in the photoreceptors (rds/+ and Bouse transgenic mice). In vitilligo mice, a similar rate of photoreceptor degeneration is induced by defect in the RPE. At the completion of this project, we expect to have defined an optimal means for recording the mouse dc-ERG in vivo, to have a thorough understanding of the processes that underlie the different components of the dc-ERG, and a more complete understanding of how these components are affected by disorders of the outer retina.

描述(申请人提供)：视网膜色素上皮(RPE)参与了正常视网膜功能所需的许多功能，包括营养物质和废物在光感受器和脉络膜循环之间的流动，视觉周期，以及脱落的外节视盘的吞噬。此外，RPE特异性基因的突变与广泛的遗传性视网膜疾病有关，这些信息正被用于开发相应的小鼠模型。在本项目中，重点是RPE对神经视网膜活动的反应产生的电反应。虽然RPE功能的特定方面可以通过使用直流耦合放大记录的视网膜电信号(ERG)来研究，但这还没有应用于小鼠。此外，关于DC-ERG的不同组成部分的来源仍然存在根本问题。在目标1中，我们将以正常野生型小鼠为研究对象，确定小鼠DC-ERG的刺激-反应特性，以及这些特性发展的时间进程。在目标2中，我们将使用转导蛋白和视紫红质的KO系，以及视锥细胞数量增加(RD7)或减少(COMAS转基因)的突变体，验证小鼠DC-ERG主要由杆状感光细胞活性启动的假设。在目标3中，我们将使用Kir4.1 KO小鼠来验证该通道参与c波产生的假设。在目标4中，我们将使用CFTRKO小鼠和腺病毒递送CFTR腺病毒构建物来验证快速振荡是由CFTR活性产生的假设。在目标5中，我们将使用DC-ERG记录来研究光感受器变性与RPE功能改变之间的关系。首先，我们将研究A2E在abcr突变小鼠中的积累如何改变RPE功能。接下来，我们将使用三个光感受器退行性变速度相似的小鼠品系来测试功能性RPE异常发生在早期阶段的假设。在两种情况下，主要缺陷存在于光感受器(rds/+和Bouse转基因小鼠)。在白癜风小鼠中，RPE的缺陷也会导致类似的光感受器退行性变。在这个项目完成时，我们希望已经定义了一种在体内记录小鼠DC-ERG的最佳方法，以彻底了解DC-ERG不同组件背后的过程，并更完整地了解这些组件如何受到视网膜外部疾病的影响。