Molecular Mechanisms of Ethanol Sensitivity in ILS and ISS Mice

ILS 和 ISS 小鼠乙醇敏感性的分子机制

• 批准号: 6967079
• 负责人: MICHAEL D BROWNING
• 金额: $ 34.05万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-08-01 至 2009-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6967079
• 关键词: GABA receptor; NMDA receptors; ethanol; genetic strain; inbreeding; laboratory mouse; neuropharmacology; pharmacogenetics; pharmacokinetics; phosphorylation; receptor expression; receptor sensitivity; sleep

DESCRIPTION (provided by applicant): We have previously shown that GABAARs in ILS mice exhibit ethanol potentiation while ethanol had no effect on GABAARs in hippocampi of ISS mice. Similarly, preliminary data presented in this proposal show that ethanol potentiates the GABAAR in cortex of ILS but not ISS mice and inhibits the NMDAR in hippocampus and cortex of ILS but not ISS mice. These dramatic differences in ILS and ISS mice in terms of the ability of ethanol to affect the GABAAR and NMDAR in hippocampus and cortex will be the principal focus of our proposal. We are proposing to study the molecular mechanisms that underlie the differences in ethanol sensitivity of the GABAAR and NMDAR in ILS and ISS mice. We anticipate that these two strains of mice will thus provide us with a unique opportunity to test hypotheses about these mechanisms. This will be the principal goal of the proposed studies. In pursuit of this goal our proposal will have three Specific Aims. Aim #1. Test the hypothesis that differences in the phosphorylation of the NMDAR and/or GABAAR in ILS and ISS mice may underlie the differences in ethanol effects on these receptors in the two strains of mice. We and others have recently shown that phosphorylation may play an important role in the ethanol sensitivity of the NMDAR and the GABAAR. And, we have shown that GABAAR and NMDAR of ILS mice are sensitive to ethanol and those of ISS mice are not. Therefore, in this aim we will compare the basal and ethanol-stimulated phosphorylation of specific subunits and/or phosphosites of the NMDAR and GABAAR in ILS and ISS mice. Aim #2. Test the hypothesis that differences in the ethanol sensitivity of the trafficking mechanisms for the NMDAR and/or GABAAR in ILS and ISS mice may underlie the differences in ethanol effects on these receptors in the two strains of mice. We and others have shown that NMDAR and GABAAR membrane trafficking may play important roles in the function of these receptors. Moreover, we have recently obtained preliminary data that ethanol reduces membrane surface expression of the NMDAR in ILS but not in ISS mice. Therefore, in this aim we will confirm and extend this observation by comparing the basal and ethanol- stimulated surface expression of the NMDAR and GABAAR in ILS and ISS mice. Aim #3 Test the hypothesis that interventions that modulate phosphorylation and/or surface expression of the NMDAR and GABAAR will reduce the effect of ethanol on GABAA R and NMDAR responses in ILS mice and and "rescue" ethanol effects on these receptors in ISS mice. Based on results from Aims 1 and 2 above, we will intervene to pharmacologically modulate phosphorylation and/or surface expression. We will then test these interventions to determine whether the biochemical differences seen in Aims 1 and 2 or either necessary or sufficient to explain the differences in ethanol effects on the evoked responses of these receptors in ILS and ISS mice.

描述(申请人提供)：我们之前已经证明，ILS小鼠中的GABAARs表现出乙醇增强作用，而乙醇对ISS小鼠海马区的GABAARs没有影响。同样，该提案中提出的初步数据显示，乙醇增强了ILS小鼠皮质中的GABAAR，而不是ISS小鼠，并抑制了ILS小鼠海马区和皮质中的NMDAR，但不抑制ISS小鼠的NMDAR。ILS和ISS小鼠在乙醇影响海马和皮质GABAAR和NMDAR的能力方面的这些显着差异将是我们提案的主要关注点。我们建议在ILS和ISS小鼠中研究GABAAR和NMDAR乙醇敏感性差异的分子机制。我们预计，这两个品系的小鼠将因此为我们提供一个独特的机会来测试关于这些机制的假说。这将是拟议研究的主要目标。为了实现这一目标，我们的提案将有三个具体目标。目的#1.验证假设：ILS和ISS小鼠NMDAR和/或GABAAR磷酸化的差异可能是乙醇对这两个品系小鼠这两种受体作用差异的基础。我们和其他人最近表明，磷酸化可能在NMDAR和GABAAR的乙醇敏感性中发挥重要作用。并且，我们已经证明ILS小鼠的GABAAR和NMDAR对乙醇敏感，而ISS小鼠不敏感。因此，在这个目标中，我们将比较ILS和ISS小鼠NMDAR和GABAAR特定亚基和/或亚基的基础磷酸化和乙醇刺激的磷酸化。目的#2.验证假设：ILS和ISS小鼠NMDAR和/或GABAAR转运机制的乙醇敏感性差异可能是这两个品系小鼠乙醇对这两种受体作用差异的基础。我们和其他人已经证明，NMDAR和GABAAR膜转运可能在这些受体的功能中发挥重要作用。此外，我们最近获得的初步数据表明，乙醇减少了ILS小鼠NMDAR膜表面的表达，但在ISS小鼠中没有。因此，在这个目标中，我们将通过比较ILS和ISS小鼠基础和乙醇刺激的NMDAR和GABAAR的表面表达来证实和扩大这一观察结果。目的#3验证以下假设：干预NMDAR和GABAAR的磷酸化和/或表面表达将减少乙醇对ILS小鼠的GABAA R和NMDAR反应的影响，并在ISS小鼠中“挽救”乙醇对这些受体的影响。基于上述目标1和2的结果，我们将进行干预，从药物上调节磷酸化和/或表面表达。然后，我们将测试这些干预措施，以确定AIMS 1和AIMS 2中出现的生化差异是否必要或足以解释乙醇对ILS和ISS小鼠这些受体的诱发反应的影响。