MICROMAPPING OF LEAD INDUCED CHANGES TO NMDA RECEPTORS

铅引起的 NMDA 受体变化的微图谱

• 批准号: 6132592
• 负责人: DIANA Leslie PETTIT
• 金额: $ 10.18万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-08-02 至 2004-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6132592
• 关键词: NMDA receptors; calcium flux; hippocampus; immunocytochemistry; laboratory rat; lead; long term potentiation; neurophysiology; neurotoxicology; protein localization; receptor expression; voltage /patch clamp

DESCRIPTION (Taken from the Candidate's Abstract) The widespread use of lead has made lead exposure a serious environmental and occupational hazard. Children are particularly vulnerable to the effects of lead and exposure can cause serious cognitive and behavioral deficits. Although lead is a known environmental neurotoxin, the physiological bases of this toxicity remain unclear. However, evidence suggests that the NMDA-type glutamate receptor function is down-regulated by lead, and this down regulation attenuates long-term potentiation (LTP), a cellular correlate of learning. Recent studies of downregulation have used binding assays and immunocytochemistry to show that binding of agonist is reduced after lead treatment. While these studies provide valuable information, they are not functional assays of receptors in intact tissue. The candidate will determine how lead modifies NMDA receptor function with a novel, high resolution method of localizing and characterizing receptor function. This method uses local photolysis of caged agonists to isolate 3 um membrane sections in living cells within brain slices. The candidate will combine whole-cell voltage clamp recordings, local photolysis, and calcium imaging to examine the effect of NMDA receptor downregulation on long-term potentiation and long-term depression. She hypothesizes that lead decreases NMDA receptor function by decreasing expression of functional receptors, changing receptor subunit composition, and altering calcium permeability, which attenuates LTP and LTD. These experiments will provide a basis for examination of the downstream processes initiated by receptor activation.

描述（取自候选人的摘要） 铅的广泛使用使铅暴露成为严重的环境，并且 职业危害。 孩子特别容易受到影响 铅和暴露会导致严重的认知和行为不足。 尽管铅是已知的环境神经毒素，但 这种毒性尚不清楚。 但是，有证据表明NMDA型 谷氨酸受体功能被铅降低，并且该下降 调节减弱了长期增强（LTP），这是一种相关的细胞 学习。 最近的下调研究使用了结合测定法和 免疫细胞化学表明激动剂的结合在铅后降低 治疗。 尽管这些研究提供了有价值的信息，但它们不是 完整组织中受体的功能测定。 候选人将确定 铅如何通过一种新颖的高分辨率方法修饰NMDA受体功能 定位和表征受体功能。 此方法使用本地 笼中激动剂的光解，分离活细胞中的3 um膜切片 在大脑切片中。 候选人将结合全细胞电压夹 记录，局部光解和钙成像，以检查 NMDA受体下调长期增强和长期的 沮丧。 她假设铅通过 功能受体的表达降低，受体亚基变化 组成和钙渗透性改变，这会减弱LTP和LTD。 这些实验将为下游的检查提供基础 受体激活引发的过程。