Basal Forebrain Cellular Mechanisms of Cortical Activation

皮质激活的基底前脑细胞机制

• 批准号: 8242210
• 负责人: Robert W McCarley
• 金额: --
• 依托单位: VA BOSTON HEALTH CARE SYSTEM
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-10-01 至 2015-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8242210
• 关键词: Acoustic Stimulation; Action Potentials; Affect; Alzheimer' s Disease; Anterior; Attention; Auditory; Auditory area; Basic Science; Binding; Biological Models; Brain; Brain Stem; Brain region; Carbachol; Cations; Cerebral cortex; Cholinergic Agonists; Coma; Data; Development; Disease; Electroencephalogram; Elements; Exhibits; Financial compensation; Fluorescence; Frequencies; Funding; Future; Genetic; Grant; Halorhodopsins; Immunohistochemistry; In Vitro; Injection of therapeutic agent; Ion Channel; Ions; Knock-in Mouse; Knock-out; Laboratories; Lesion; Light; Measures; Mediating; Memory; Methodology; Methods; Military Personnel; Molecular; Mus; Muscarinic M3 Receptor; Muscarinics; Neurons; Neurotransmitter Receptor; Neurotransmitters; Parvalbumins; Patients; Perception; Polysomnography; Population; Procedures; REM Sleep; RNA; Receptor Activation; Regulation; Research; Role; Schizophrenia; Sensory; Series; Sleep; Sleep Deprivation; Sleep Disorders; Sleep Wake Cycle; Slice; Small Interfering RNA; Sodium; Symptoms; Synapses; System; Techniques; Testing; Toxin; Veterans; Viral Vector; Visual Cortex; Wakefulness; Work; alertness; basal forebrain; basal forebrain cholinergic neurons; base; cell assembly; cell type; cholinergic; cholinergic neuron; cingulate cortex; executive function; gamma-Aminobutyric Acid; hypocretin; improved; in vivo; information processing; neural circuit; novel; novel strategies; optogenetics; orexin B receptor; patch clamp; programs; receptor; recombinase; research study; response; sleep regulation; therapeutic target; tool; transcriptional coactivator p75; voltage clamp

DESCRIPTION (provided by applicant): How do the states of wakefulness and sleep enhance the processing of information? The answer to this question involves the ability of the brain to synchronize the activities of assemblies of neurons by means of neuronal oscillations so that salient pieces of information are bound together in coherent percepts and synaptic connections between related neurons are strengthened, as originally proposed by Donald Hebb. The frequency, regional distribution and amplitude of such neuronal oscillations vary across the sleep-wake cycle. In particular, gamma oscillations (30-80 Hz or broader, centered on 40 Hz) are a prominent feature of the electroencephalogram (EEG) during waking and REM sleep. These oscillations are thought to be essential for brain functions such as attention, perception, and memory formation. Work from our group and from others has demonstrated gamma abnormalities in prefrontal and primary sensory (auditory and visual) cortices in schizophrenic patients. Furthermore, gamma deficits are a prominent feature of sleep disorders, coma, and Alzheimer's disease, other conditions prevalent in veterans and military personnel. Modulation of gamma oscillations thus represents a promising therapeutic target to treat symptoms of these disorders. This proposal focuses on the modulation of cortical activation and gamma oscillations by the basal forebrain (BF) neuronal projections to the cerebral cortex, since, in a recent study, extensive lesions of the BF region revealed dramatic reductions in cortical activation/gamma activity leading to a coma-like state. While such lesions point to the importance of BF, they do not tell us which specific BF cell types are important for cortical activation, how BF is influenced by other brain regions and neurotransmitters, and which circuits and neurotransmitters would be optimal treatment targets. Building on the methodologies developed in the previous grant cycle and following our laboratory's strength and track record of using a multilevel approach, the proposed experiments use integrated molecular, in vitro, and in vivo (systems) methods in mice to provide optimal understanding of the neural circuits studied. In the first series of experiments novel 'optogenetic light- activated ion channels will be inserted into specific BF subpopulations (cholinergic and GABAergic neurons containing parvalbumin) to study the effect of activating or inhibiting these specific neuronal cell types on cortical activation/gamma activity. Polysomnographic recordings will determine the effect of these manipulations on sleep and wakefulness. Cortical local field potential (LFP) recordings will be used to gain a precise determination of local gamma oscillations in three different cortical regions affected by sleep deprivation and exhibiting abnormalities in schizophrenia. In addition, Fos immunohistochemistry will be used to provide a spatial and cell-type specific analysis of cortical activation following light stimulation of theseBF subpopulations. Following our successful use of small interfering RNA (siRNA) in the brainstem, the same technique will be used to knockdown orexin receptors in the BF and reveal their role in sleep-wake control, providing reversibility without the potential confound of developmental compensation often seen with constitutive knockouts. The selective toxin mu p75-saporin will be used to investigate the role of cholinergic BF neurons in the regulation of wakefulness, and the effect of orexins. In the last series of experiments we will use GAD67-GFP knock-in mice, a novel genetic tool validated in the previous grant cycle, to identify cortically projecting BF GABA neurons in vitro. Using patch-clamp recordings we will reveal their modulation by cholinergic and orexinergic compounds and determine the receptors and ion channels activated. In summary, we propose to use state-of-the-art methods to identify the cellular and molecular components of the BF projections to the cortex modulating wakefulness and cortical gamma activity. We thereby lay the groundwork for targeted therapies to improve alertness, attention, and executive function in conditions that affect the Veteran population such as schizophrenia, Alzheimer's disease and sleep disorders. PUBLIC HEALTH RELEVANCE: Recent evidence suggests cortical activation and gamma rhythms are abnormal in several diseases prevalent in veterans and military personnel, including sleep disorders, schizophrenia, and coma. The research proposed will lay the ground work for targeted therapies to improve alertness, attention, and executive function in patients suffering from these conditions. The research focuses on how specific cortically projecting basal forebrain neurons modulate wakefulness, cortical activation and electroencephalographic oscillations in the gamma frequency range (30-120 Hz). The experiments proposed will employ multilevel, state of the art, novel approaches including optogenetic, siRNA, and in vitro pharmacological procedures to identify the neurotransmitter receptors and effector systems that can be targeted for future pharmacological, or genetic treatments, to modulate cortical activation and gamma activity.

描述（由申请人提供）： 清醒和睡眠状态如何增强信息处理？这个问题的答案涉及大脑通过神经元振荡同步神经元集合活动的能力，以便将显着的信息以连贯的感知结合在一起，并加强相关神经元之间的突触连接，正如唐纳德最初提出的那样赫布。这种神经元振荡的频率、区域分布和幅度在整个睡眠-觉醒周期中各不相同。特别是，伽马振荡（30-80 Hz 或更宽，以 40 Hz 为中心）是清醒和快速眼动睡眠期间脑电图 (EEG) 的一个显着特征。这些振荡被认为对于注意力、感知和记忆形成等大脑功能至关重要。我们小组和其他人的工作已经证明精神分裂症患者的前额叶和初级感觉（听觉和视觉）皮层存在伽玛异常。此外，伽玛缺乏是睡眠障碍、昏迷和阿尔茨海默病以及退伍军人和军事人员中常见的其他疾病的一个显着特征。因此，伽马振荡的调节代表了治疗这些疾病症状的有希望的治疗靶点。 该提案的重点是通过基底前脑（BF）神经元投射到大脑皮层来调节皮质激活和伽玛振荡，因为在最近的一项研究中，BF区域的广泛病变揭示了皮质激活/伽玛活动的急剧减少，导致类似昏迷的状态。虽然这些病变指出了 BF 的重要性，但它们并没有告诉我们具体是哪个 BF 细胞 类型对于皮质激活、BF 如何受到其他大脑区域和神经递质的影响以及哪些回路和神经递质将是最佳治疗目标非常重要。基于上一个资助周期开发的方法，并遵循我们实验室使用多层次方法的实力和跟踪记录，拟议的实验在小鼠中使用集成的分子、体外和体内（系统）方法，以提供对神经网络的最佳理解。研究过的电路。在第一个系列实验中，新型“光遗传学光激活离子通道”将被插入特定的 BF 亚群（含有小白蛋白的胆碱能和 GABA 能神经元）中，以研究激活或抑制这些特定神经元细胞类型对皮质激活/γ 活性的影响。多导睡眠图记录将确定这些操作对睡眠和觉醒的影响。皮质局部场电位（LFP）记录将用于精确确定受睡眠剥夺影响并表现出精神分裂症异常的三个不同皮质区域的局部伽马振荡。此外，Fos 免疫组织化学将用于对这些 BF 亚群光刺激后皮质激活进行空间和细胞类型特异性分析。继我们在脑干中成功使用小干扰 RNA (siRNA) 后，同样的技术将用于敲低 BF 中的食欲素受体，并揭示它们在睡眠-觉醒控制中的作用，提供可逆性，而不会出现常见的发育补偿的潜在混淆。本构型淘汰赛。选择性毒素mu p75-皂草素将用于研究胆碱能BF神经元在觉醒调节中的作用以及食欲素的作用。在最后一系列实验中，我们将使用 GAD67-GFP 敲入小鼠（一种在上一个资助周期中验证的新型遗传工具）来识别皮质投射 BF GABA 体外的神经元。使用膜片钳记录，我们将揭示胆碱能和食欲能化合物对它们的调节，并确定激活的受体和离子通道。 总之，我们建议使用最先进的方法来识别 BF 投射到皮质调节觉醒和皮质伽玛活动的细胞和分子成分。因此，我们为靶向治疗奠定了基础，以改善影响退伍军人群体的警觉性、注意力和执行功能，例如精神分裂症、阿尔茨海默病和睡眠障碍。 公共卫生相关性： 最近的证据表明，在退伍军人和军事人员中常见的几种疾病中，皮质激活和伽马节律异常，包括睡眠障碍、精神分裂症和昏迷。拟议的研究将为靶向治疗奠定基础，以提高患有这些疾病的患者的警觉性、注意力和执行功能。该研究的重点是特定的皮质投射基底前脑神经元如何在伽马频率范围（30-120 Hz）内调节觉醒、皮质激活和脑电图振荡。所提出的实验将采用多层次、最先进的新颖方法，包括光遗传学、siRNA 和体外药理学程序，以识别神经递质受体和效应系统，这些受体和效应系统可以作为未来药理学或遗传治疗的目标，以调节皮质激活和伽马射线。活动。