MODERATE ETHANOL PRENATALLY ON NMDA PHOSPHORYLATION

产前适度乙醇对 NMDA 磷酸化

• 批准号: 6371480
• 负责人: STEVEN W LESLIE
• 金额: $ 27.76万
• 依托单位: UNIVERSITY OF TEXAS AT AUSTIN
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-08-01 至 2004-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6371480
• 关键词: NMDA receptors; RNase protection assay; SDS polyacrylamide gel electrophoresis; brain metabolism; cerebellum; cerebral cortex; dosage; embryo /fetus toxicology; ethanol; fetal alcohol syndrome; glutamates; hippocampus; immunoprecipitation; laboratory rat; messenger RNA; newborn animals; phosphorylation; protein kinase; protein structure function; receptor binding; receptor expression; vertebrate embryology; western blottings

Studies in our laboratory and by others indicate that prenatal and early postnatal ethanol exposure results in a significant reduction of NMDA receptor function and number. NMDA receptors are linked with important aspects of brain development and learning and memory. Ethanol-related deficits in NMDA function, therefore, may be of key importance not only in the severe cognitive and behavioral deficiencies of fetal alcohol syndrome (FAS) but also in alcohol-related neurodevelopmental disorders (ARND) typically expressed as behavioral symptoms associated with fetal alcohol effects (FAE). We have recently found that decreases in NMDA receptor function resulting from prenatal ethanol exposure in rats are accompanied by reductions in some, but not all, of the subunits comprising the NMDA receptor complex. NMDAR2A and NMDAR2B subunits are significantly reduced, while the NMDAR1 subunit is unaffected. Studies conducted thus far have examined the effects of high doses of ethanol prenatally and postnatally on NMDA receptor function and subunit levels. Studies proposed in specific aims 1 through 4 are designed to determine the dose-response relationships of prenatal ethanol treatment on 1) functional measures of NMDA receptor activation using fura-2 loaded dissociated neurons and H-MK801 binding, 2) NMDAR1 and NMDAR2 subunit protein (Western blot analysis) and messenger RNA levels (RNase protection assay), and 3) changes in NMDA receptor subunit composition as measured by immunoprecipitation studies. Specific aim 4 will examine the relationship(s) of NMDA receptor subunit changes with changes in subunit phosphorylation. The overall hypothesis of this proposal is that prenatal ethanol exposure, even at modest concentrations, will result in demonstrable deficits in the function of NMDA receptors. We expect the magnitude of the deficits to be dose-related. It is hypothesized further that ethanol's actions in this regard may be linked with abnormalities of NMDA receptor phosphorylation.

我们实验室和其他人的研究表明，产前和出生后早期酒精暴露会导致NMDA受体功能和数量的显着下降。NMDA受体与大脑发育、学习和记忆的重要方面有关。因此，酒精相关的NMDA功能缺陷可能不仅在胎儿酒精综合征(Fas)的严重认知和行为缺陷中起关键作用，而且在酒精相关神经发育障碍(ARND)中也可能起关键作用，ARND通常表现为与胎儿酒精效应(FAE)相关的行为症状。我们最近发现，孕期酒精暴露导致的大鼠NMDA受体功能的下降伴随着组成NMDA受体复合体的一些但不是全部亚单位的减少。NMDAR2A和NMDAR2B亚基显著减少，而NMDAR1亚基未受影响。到目前为止，已经进行的研究检查了产前和出生后高剂量乙醇对NMDA受体功能和亚单位水平的影响。在特定目标1至4中提出的研究旨在确定产前酒精治疗对以下方面的剂量-反应关系：1)利用Fura-2负载的分离神经元和H-MK801结合来激活NMDA受体的功能指标，2)NMDAR1和NMDAR2亚单位蛋白(Western印迹分析)和信使RNA水平(RNase保护试验)，以及3)免疫沉淀研究测量的NMDA受体亚单位组成的变化。具体目标4将研究N-甲基-D-天冬氨酸受体亚单位变化与亚单位磷酸化变化的关系(S)。这一提议的总体假设是，产前接触酒精，即使是适度的浓度，也会导致NMDA受体功能的明显缺陷。我们预计赤字的规模将与剂量有关。进一步推测，乙醇在这方面的作用可能与NMDA受体磷酸化的异常有关。