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（由申请人提供）：我们之前已经证明ILS小鼠中的GABAAR表现出乙醇增强作用，而乙醇对ISS小鼠海马中的GABAAR没有影响。同样，该提案中提出的初步数据表明，乙醇增强了 ILS 小鼠（而非 ISS 小鼠）皮层中的 GABAAR，并抑制 ILS 小鼠（而非 ISS 小鼠）海马和皮层中的 NMDAR。 ILS 和 ISS 小鼠在乙醇影响海马和皮质中 GABAAR 和 NMDAR 的能力方面的显着差异将是我们提案的主要焦点。我们打算研究 ILS 和 ISS 小鼠中 GABAAR 和 NMDAR 乙醇敏感性差异的分子机制。我们预计这两种小鼠品系将为我们提供一个独特的机会来检验有关这些机制的假设。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。目标#1。检验以下假设：ILS 和 ISS 小鼠中 NMDAR 和/或 GABAAR 磷酸化的差异可能是乙醇对这两种小鼠品系中这些受体的影响差异的基础。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。而且，我们已经证明 ILS 小鼠的 GABAAR 和 NMDAR 对乙醇敏感，而 ISS 小鼠则不然。因此，在此目的中，我们将比较 ILS 和 ISS 小鼠中 NMDAR 和 GABAAR 的特定亚基和/或磷酸位点的基础磷酸化和乙醇刺激的磷酸化。目标#2。检验以下假设：ILS 和 ISS 小鼠中 NMDAR 和/或 GABAAR 运输机制的乙醇敏感性差异可能是乙醇对这两种小鼠品系中这些受体的影响差异的基础。我们和其他人已经证明，NMDAR 和 GABAAR 膜运输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，乙醇会降低 ILS 小鼠的膜表面 NMDAR 表达，但不会降低 ISS 小鼠的膜表面表达。因此，为了这个目的，我们将通过比较 ILS 和 ISS 小鼠中 NMDAR 和 GABAAR 的基础和乙醇刺激的表面表达来确认和扩展这一观察结果。目标 #3 检验以下假设：调节 NMDAR 和 GABAAR 的磷酸化和/或表面表达的干预措施将减少乙醇对 ILS 小鼠中 GABAA R 和 NMDAR 反应的影响，并“拯救”乙醇对 ISS 小鼠中这些受体的影响。基于上述目标 1 和 2 的结果，我们将进行干预以药理学调节磷酸化和/或表面表达。然后，我们将测试这些干预措施，以确定目标 1 和 2 中看到的生化差异是否有必要或足以解释乙醇对 ILS 和 ISS 小鼠中这些受体诱发反应的影响的差异。