The Role of Neurotensin-Expressing Neurons of the Extended Ventrolateral Preoptic Nucleus in REM Sleep Regulation

扩展腹外侧视前核表达神经降压素的神经元在快速眼动睡眠调节中的作用

• 批准号: 10663472
• 负责人: Roberto De Luca
• 金额: $ 8.65万
• 依托单位: BETH ISRAEL DEACONESS MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-02-06 至 2025-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10663472
• 关键词: Animals; Applications Grants; Area; Automobile Driving; Axon; Brain; Brain Stem; Cell Nucleus; Cells; Data; Disinhibition; Dorsal; Electrophysiology (science); Follow-Up Studies; Future; Galanin; Generations; Genetic; Genetic Transcription; Goals; Grant; In Situ Hybridization; In Vitro; Knowledge; Label; Lesion; Maintenance; Maps; Medial; Mediating; Methods; Midbrain structure; Mus; Neurons; Neuropeptides; Neurotensin; Optics; Output; Pathway interactions; Pontine structure; Population; Preoptic Areas; Process; REM Sleep; Research; Research Project Grants; Reticular Formation; Role; Sleep; Sleeplessness; Slice; Synapses; Testing; Time; Work; anatomical tracing; base; design; experimental study; follow-up; gamma-Aminobutyric Acid; in vivo; insight; interest; locus ceruleus structure; midbrain central gray substance; neural circuit; non rapid eye movement; novel; optogenetics; postsynaptic; postsynaptic neurons; preoptic nucleus; public repository; response; secondary analysis; selective expression; single-cell RNA sequencing; sleep regulation; tool; transcriptomics

Project Summary/Abstract Sleep is an active process requiring the participation of delimited nodes of sleep-promoting cell populations. Work over the last twenty years has demonstrated that galanin expressing neurons in the ventrolateral preoptic (VLPOGal) nucleus are necessary for normal sleep. While a portion of VLPO galanin neurons is concentrated in a cluster, the so-called VLPO core (cVLPO), others are scattered dorsally and medially to that core, a region that came to be known as the extended VLPO (eVLPO). Lesion and optogenetic studies have demonstrated that the galanin expressing neurons in the cVLPO and those in the eVLPO are two functionally distinct cell groups with the cVLPOGal neurons required for non-REM sleep (NREM) while the eVLPOGal neurons required for REM sleep. Anatomical tracing studies have shown that the eVLPOGal neurons innervate brainstem nuclei implicated in REM sleep regulation and through these descending projections, the eVLPOGal neurons are thought to promote REM sleep by the disinhibition of the REM-generating neurons in the pontine reticular formation. There remain however several fundamental gaps in our understanding of the cellular and synaptic basis by which eVLPOGal neurons drive REM sleep. Studying the eVLPOGal population has been proven to be quite challenging as the cVLPO and the eVLPO are small regions located in close proximity and until now, there were no markers for selective targeting. We have recently discovered a potential marker for the eVLPOGal neurons that will allow us to manipulate the eVLPOGal neurons independently from their neighboring cVLPOGal neurons. Specifically, we have found that: 1) the eVLPOGal neurons selectively express the neuropeptide neurotensin and, 2) that chemogenetic inhibition of the neurotensin eVLPO neurons reduces REM sleep. We have also found that eVLPO neurotensin neurons send robust projections to regions of the midbrain and pons that are known to suppress REM sleep including the ventrolateral periaqueductal gray (vlPAG) and the locus coeruleus (LC). On the basis of these results, we propose that the eVLPO neurotensin neurons promote REM sleep by disinhibiting REM-generating neurons in the pontine reticular formation via inhibition of GABA neurons of the vlPAG and monoaminergic neurons of the LC. The current proposal thus seeks to identify, first in vitro and then in vivo, the brainstem efferent outputs through which the eVLPO neurotensin neurons drive REM sleep. To do so, we will first employ, in Specific Aims 1, in vitro circuit mapping to identify the postsynaptic neurons that are targeted by the eVLPO neurotensin neurons. In Specific Aim 2, we will use in vivo optogenetics to test whether the circuits first identified in the in vitro studies are sufficient to produce REM sleep. Given the large knowledge gap this proposal seeks to fill, we expect results from this work to provide 1) an important interpretative framework for future studies on the eVLPO neurotensin pathways that are necessary and sufficient for promoting REM sleep and 2) more generally, a novel insight into the role of the preoptic region in REM sleep regulation.

项目总结/摘要 睡眠是一个主动的过程，需要一定范围内的促眠细胞参与 人口。过去二十年的工作已经证明，表达甘丙肽的神经元中， 腹外侧视前核（VLPOGal）是正常睡眠所必需的。而一部分VLPO甘丙肽 神经元集中在一个簇中，即所谓的VLPO核心（cVLPO），其他神经元分散在背侧， 在核心的中间，一个被称为扩展VLPO（eVLPO）的区域。病变和光遗传学 研究表明，cVLPO和eVLPO中表达甘丙肽的神经元是两种， 非REM睡眠（NREM）所需的cVLPOGal神经元的功能不同的细胞群，而 eVLPOGal神经元需要REM睡眠。解剖追踪研究表明，eVLPOGal神经元 神经支配脑干核团，这些核团参与REM睡眠调节，通过这些下行投射， eVLPOGal神经元被认为是通过释放REM产生神经元的抑制来促进REM睡眠的。 脑桥网状结构然而，在我们对《公约》的理解方面仍然存在一些根本性的差距。 eVLPOGal神经元驱动REM睡眠的细胞和突触基础。研究eVLPOGal群体 由于cVLPO和eVLPO是位于近距离的小区域， 到目前为止，还没有用于选择性靶向的标记。我们最近发现了一种潜在的 eVLPOGal神经元的标记物，这将使我们能够独立地操纵eVLPOGal神经元， 它们邻近的cVLPOGal神经元。具体而言，我们已经发现：1）eVLPOGal神经元选择性地 表达神经肽神经降压素，2）神经降压素eVLPO神经元的化学发生抑制 减少REM睡眠。我们还发现，eVLPO神经降压素神经元发送强大的投射到区域 中脑和脑桥，包括腹外侧导水管周围， 灰质（vlPAG）和蓝斑（LC）。在这些结果的基础上，我们提出eVLPO 神经降压素神经元通过解除对脑桥网状核中REM产生神经元的抑制来促进REM睡眠 通过抑制vlPAG的GABA神经元和LC的单胺能神经元形成。当前 因此，该提案试图首先在体外然后在体内鉴定脑干传出输出， eVLPO神经降压素神经元驱动REM睡眠。为此，我们将首先在特定目标1中采用体外电路 映射以鉴定由eVLPO神经降压素神经元靶向的突触后神经元。在特定 目的2，我们将使用体内光遗传学来测试在体外研究中首次鉴定的电路是否是 足以产生快速眼动睡眠鉴于这一提议试图填补的巨大知识空白，我们期待着结果 从这项工作提供1）一个重要的解释框架，为未来的研究eVLPO神经降压素 这些通路对于促进REM睡眠是必要和充分的，2）更普遍地，一个新的见解， 视前区在REM睡眠调节中的作用。