Catecholaminergic Signaling in Normal Cognition, Aging and Models of Alzheimer's Disease

总结 阿尔茨海默氏病（AD）和其他痴呆是一个巨大的和迅速增长的社会负担，由于 人口老龄化。这种衰老的发生部分是因为现代医学已经确定了危险因素 以及其他疾病的治疗方法，但不包括AD因此，有一个伟大的和未满足的需要这样做。一 AD和非痴呆性衰老的标志性症状是记忆受损，包括恢复。此外，一些 在AD中发现的最早的神经病理学是在提供神经调质多巴胺（DA）的系统内 和去甲肾上腺素（NE）到大脑（包括海马体，陈述性/情景记忆的中心）。 最大的脑干肾上腺素能核是蓝斑（LC），它提供所有的NE和a 在背侧海马中发现的DA的相当大的部分。LC在正常老化中也会受到影响。 因此，本提案的目标是更好地理解LC衍生DA的作用和机制， NE调节陈述性/情景记忆的编码和提取。为了实现这一目标，药理学 基因操作将在啮齿类动物中进行，因为啮齿类动物有很好的行为范例， 依赖于校园记忆我们的初步研究表明，所有三种β-肾上腺素能受体 在海马中，NE激活的神经元在促进记忆提取中起着关键作用。他们还建议 肾上腺素能多巴胺是依赖于海马的记忆所必需的。因此，第一个目标将审查 β-肾上腺素能受体促进海马依赖性记忆的分子和细胞机制 使用药理学和遗传学相结合的方法。血管内皮细胞中β受体的亚细胞定位 海马也将被确定。第二个目的是研究依赖于大学校园的 通过药理学和遗传学相结合的方法研究“肾上腺素能”多巴胺对记忆的影响。第三个目标将审查 增强DA和NE信号传导的药物在AD和衰老模型中促进记忆的能力。的 这些目标的完成将使我们更好地理解记忆编码和提取是如何被促进的 在海马体中，并最终可能提示增强AD和衰老记忆的潜在靶点。

SUMMARY Alzheimer’s disease (AD) and other dementias are a substantial and rapidly growing societal burden due to the aging of our population. This aging has occurred in part because modern medicine has identified risk factors and treatments for many other diseases, but not for AD. Thus there is a great and unmet need to do so. A hallmark symptom of AD and aging without dementia is impaired memory, including retrieval. Further, some of the earliest neuropathology found in AD is within the systems that provide the neuromodulators dopamine (DA) and norepinephrine (NE) to the brain (including the hippocampus, a center for declarative/episodic memory). The largest brainstem adrenergic nucleus is the locus coeruleus (LC), which supplies all of the NE and a substantial portion of the DA found in the dorsal hippocampus. The LC can also be affected in normal aging. As such, the goal of this proposal is to better understand the roles and mechanisms by which LC-derived DA and NE modulate the encoding and retrieval of declarative/episodic memory. Toward this goal, pharmacologic and genetic manipulations will be performed in rodents, for which there are excellent behavioral paradigms that rely on hippocampus-dependent memory. Our preliminary studies indicate that all three -adrenergic receptors that are activated by NE play a critical role in the hippocampus to promote memory retrieval. They also suggest that adrenergic DA is required for hippocampus-dependent memory. Thus the first aim will examine the molecular and cellular mechanisms by which -adrenergic receptors promote hippocampus-dependent memory using combined pharmacologic and genetic approaches. Subcellular localization of  receptors in the hippocampus will also be determined. The second aim will examine the modulation of hippocampus-dependent memory by “adrenergic” DA using combined pharmacologic and genetic approaches. The third aim will examine the ability of drugs that enhance DA and NE signaling to promote memory in models of AD and aging. The completion of these aims will provide a better understanding of how memory encoding and retrieval is facilitated within the hippocampus, and ultimately may suggest potential targets for enhancing memory in AD and aging.