我们感谢我们的同事参加工作的总结。这项工作是支持的补助金从德意志研究联合会（SFB 894），的DFG Schwerpunktprogramm 1392“综合分析的嗅觉和德国大众汽车基金会（TLZ）。 TLZ是一个利希滕贝格教授，德国大众汽车基金会。

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J. 74, 1591-1599 (1998).</li><li>Wen, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+characterization+of+genetically+labeled+gonadotropes.">Functional characterization of genetically labeled gonadotropes.</a> Endocrinology. 149, 2701-2711 (2008).</li><li>Paxinos, G., Franklin, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The mouse brain in stereotaxic coordinates. , (2001).</li><li>Tirindelli, R., Dibattista, M., Pifferi, S., Menini, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=From+pheromones+to+behavior.">From pheromones to behavior.</a> Physiol. Rev. 89, 921-956 (2009).</li><li>Kelliher, K. R., Wersinger, S. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Olfactory+regulation+of+the+sexual+behavior+and+reproductive+physiology+of+the+laboratory+mouse:+effects+and+neural+mechanisms.">Olfactory regulation of the sexual behavior and reproductive physiology of the laboratory mouse: effects and neural mechanisms.</a> ILAR J. 50, 28-42 (2009).</li><li>Yoon, H., Enquist, L. W., Dulac, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Olfactory+inputs+to+hypothalamic+neurons+controlling+reproduction+and+fertility.">Olfactory inputs to hypothalamic neurons controlling reproduction and fertility.</a> Cell. 123, 669-682 (2005).</li><li>Boehm, U., Zou, Z., Buck, L. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Feedback+loops+link+odor+and+pheromone+signaling+with+reproduction.">Feedback loops link odor and pheromone signaling with reproduction.</a> Cell. 123, 683-695 (2005).</li><li>Wilson, J. M., Dombeck, D. A., Diaz-Rios, M., Harris-Warrick, R. M., Brownstone, R. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Two-photon+calcium+imaging+of+network+activity+in+XFP-expressing+neurons+in+the+mouse.">Two-photon calcium imaging of network activity in XFP-expressing neurons in the mouse.</a> J. Neurophysiol. 97, 3118-3125 (2007).</li><li>Hu, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Detection+of+near-atmospheric+concentrations+of+CO2+by+an+olfactory+subsystem+in+the+mouse.">Detection of near-atmospheric concentrations of CO2 by an olfactory subsystem in the mouse.</a> Science. 317, 953-957 (2007).</li><li>Perez, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+transient+receptor+potential+channel+expressed+in+taste+receptor+cells.">A transient receptor potential channel expressed in taste receptor cells.</a> Nat. Neurosci. 5, 1169-1176 (2002).</li><li>Trollinger, D. R., Cascio, W. E., Lemasters, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selective+loading+of+Rhod+2+into+mitochondria+shows+mitochondrial+Ca2++transients+during+the+contractile+cycle+in+adult+rabbit+cardiac+myocytes.">Selective loading of Rhod 2 into mitochondria shows mitochondrial Ca2+ transients during the contractile cycle in adult rabbit cardiac myocytes.</a> Biochem Biophys. Res. Commun. 236, 738-742 (1997).</li><li>Meshik, X. A., Hyrc, K. L., Goldberg, M. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Properties+of+Asante+Calcium+Red+-+a+novel+ratiometric+indicator+with+long+excitation+wavelength.">Properties of Asante Calcium Red - a novel ratiometric indicator with long excitation wavelength.</a> , (2010).</li></ol>

没有利益冲突的声明。

在神经科学中的一个主要问题是了解大脑是如何处理社会信息化。一个主要的编码嗅觉或信息素信号源所需的信息社会的认可。这些信号在鼻子和识别的信号在大脑中，尤其是下丘脑的神经元群体的检测，发挥了关键作用，许多社会进程和影响的激素和其他神经内分泌因子13-16。的一个重要障碍等脑区的神经元的反应，下丘脑多功能与多个神经元细胞核的分析是感兴趣的特定神经元的鉴定...

There was a typo in the abstract of <a href="http://www.jove.com/video/4213">Imaging Calcium Responses in GFP-tagged Neurons of Hypothalamic Mouse Brain Slices</a>.

Erratum: Imaging Calcium Responses in GFP-tagged Neurons of Hypothalamic Mouse Brain Slices

<table border="1"><tbody><tr><td> 名称 </td><td> 公司 </td><td> 猫。 N° </td></tr><tr><td>洋菜</td><td>西格玛</td><td> A1296 </td></tr><tr><td> Fura-red/AM </td><td> Invitrogen公司</td><td> F-3021 </td></tr><tr><td>聚醚F-127 </td><td>西格玛</td><td> P2443 </td></tr><tr><td>二甲基亚砜</td><td> Fisher Scientific则</td><td> BP231 </td></tr><tr><td>振动刀片切片岩狸V 50 </td><td>蔡司</td><td> 9770170 </td></tr><tr><td>冷却装置CU切片岩狸V 50 65 </td><td>蔡司</td><td> 9920120 </td></tr><tr><td> O 2 / CO 2孵化器，CB210-UL </td><td>宾德</td><td> 0019389 </td></tr><tr><td>超级胶水，乐泰406TM </td><td> ·亨克尔</td><td> 142580 </td></tr><tr><td>双铲，勺形</td><td>Bochem </td><td> 3182 </td></tr><tr><td> Microspoon铲，勺形</td><td> Bochem </td><td> 3344 </td></tr><tr><td>春风似剪刀，莫里亚Vannas-沃尔夫 - 7毫米的刀片</td><td>精细科学工具</td><td> 15370-52 </td></tr><tr><td>春风似剪刀，维纳斯 - 3毫米的刀片</td><td>精细科学工具</td><td> 15000-00 </td></tr><tr><td>瓦格纳剪刀</td><td>精细科学工具</td><td> 14071-12 </td></tr><tr><td>医疗钳，杜蒙7B </td><td>精细科学工具</td><td> 11270-20 </td></tr><tr><td>大矩形的开放式沐浴室（RC-27） </td><td>华纳仪器</td><td> 64-0238 </td></tr><tr><td>共聚焦显微镜BioRad公司光辉2100 </td><td>蔡司</td><td>不适用</td></tr></tbody></table>

imaging calcium responses in gfp-tagged neurons of hypothalamic mouse brain slices

在我们的知识尽管一个巨大的增加有关的机制，在大脑中的信息的编码，一个中心问题的确切分子步骤，以及特定的神经元的活性，在如下丘脑保持脑区的多功能核。这个问题包括参与各种神经激素信号转导通路的调节成分的分子识别。立面图细胞内Ca 2 +在调节神经元的敏感性，发挥重要的作用，无论是在水平的信号转导，和在突触站点。 出现了新的工具，以帮助识别特定的启动子的控制下表达绿色荧光蛋白（GFP）无数的神经元在大脑的神经元。若要监视空间和时间上的刺激诱 ​​导的Ca 2 +的响应在GFP-标记的神经元，非绿色荧光的Ca 2 +指示剂染料Ň要使用的电火工品。此外，激光共聚焦显微镜是一个喜爱的成像单个神经元的方法，由于其能力，可视化神经元的组织内，并在不同的平面的深度限制满分的聚焦荧光组织切片。比例式的Ca 2 +指示剂fura-2的组合已被用于与GFP标记的神经元1。然而，染料通过紫外线（UV）光被激发。 UV光的激光和光穿透深度有限的成本阻碍了它的使用在许多实验室中。此外，GFP荧光可能会干扰与fura-2的信号2。因此，我们决定使用红色荧光的Ca 2 +指示剂染料。巨大的笔画呋喃红色移位允许使用一个单一的激发波长与GFP组合的红色荧光的多色分析。我们有以前了良好的效果，使用呋喃结合红色与绿色荧光蛋白标记的嗅觉神经元。嗅觉组织切片的协议似乎工作电子邮件qually下丘脑神经元。呋喃红色的Ca 2 +成像也成功地结合GFP标记的胰岛β细胞和GFP标记的受体表达的HEK细胞5,6。一个小怪癖的呋喃红是在650 nm，其荧光强度降低，一旦指标结合钙7。因此，具有相对高的静息神经元低的Ca 2 +浓度的荧光强度。应当指出，红色，其他Ca 2 +的指示剂染料存在的或正在开发的，这可能给在不同的神经元和大脑区域更好的或改进的结果。

Watch this Scientific Journal Video about Imaging Calcium Responses in GFP-tagged Neurons of Hypothalamic Mouse Brain Slices at JoVE.com

Imaging Calcium Responses in GFP-tagged Neurons of Hypothalamic Mouse Brain Slices

在这个协议中，我们更新了最新进展，成像钙<sup&gt; 2 +</sup&gt;绿色荧光蛋白标记的神经元在脑组织切片，使用红色荧光钙信号<sup&gt; 2 +</sup&gt;指示剂染料。

在GFP标记的下丘脑神经元的小鼠脑片成像钙反应

Despite an enormous increase in our knowledge about the mechanisms underlying the encoding of information in the brain, a central question concerning the ...

imaging-calcium-responses-gfp-tagged-neurons-hypothalamic-mouse-brain

Research

JoVE Journal

Neuroscience

17.8K 次观看.  University of Saarland, Homburg, Germany. 在这个协议中，我们更新了最新进展，成像钙 2 +绿色荧光蛋白标记的神经元在脑组织切片，使用红色荧光钙信号 2 +指示剂染料。

视频: Imaging Calcium Responses in GFP-tagged Neurons of Hypothalamic Mouse Brain Slices

Dual Somatic Recordings from Gonadotropin-Releasing Hormone (GnRH) Neurons Identified by Green Fluorescent Protein (GFP) in Hypothalamic Slices

Gonadotropin-Releasing Hormone (GnRH) is a small neuropeptide that regulates pituitary release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). These gonadotropins are essential for the regulation of reproductive function. The GnRH-containing neurons are distributed diffusely throughout the hypothalamus and project to the median eminence where they release GnRH from their axon terminals into the hypophysiotropic portal system (1). In the portal capillaries, GnRH travels to the anterior pituitary gland to stimulate release of gonadotropins into systemic circulation. GnRH release is not continuous but rather occurs in episodic pulses. It is well established that the intermittent manner of GnRH release is essential for reproduction (2, 3).
Coordination of activity of multiple GnRH neurons probably underlies GnRH pulses. Total peptide content in GnRH neurons is approximately 1.0 pg/cell (4), of which 30% likely comprises the releasable pool. Levels of GnRH during a pulse (5, 6), suggest multiple GnRH neurons are probably involved in neurosecretion. Likewise, single unit activity extracted from hypothalamic multi-unit recordings during LH release indicates changes in activity of multiple neurons (7). The electrodes with recorded activity during LH pulses are associated with either GnRH somata or fibers (8). Therefore, at least some of this activity arises from GnRH neurons.
The mechanisms that result in synchronized firing in hypothalamic GnRH neurons are unknown. Elucidating the mechanisms that coordinate firing in GnRH neurons is a complex problem. First, the GnRH neurons are relatively few in number. In rodents, there are 800-2500 GnRH neurons. It is not clear that all GnRH neurons are involved in episodic GnRH release. Moreover, GnRH neurons are diffusely distributed (1). This has complicated our understanding of coordination of firing and has made many technical approaches intractable. We have optimized loose cell-attached recordings in current-clamp mode for the direct detection of action potentials and developed a recording approach that allows for simultaneous recordings from pairs of GnRH neurons.

Dual Somatic Recordings from Gonadotropin-Releasing Hormone GnRH Neurons Identified by Green Fluorescent Protein GFP in Hypothalamic Slices

Activity in neuronal systems often requires synchronous action potential discharges from neurons within a specific population. For example, pulses of gonadotropin-releasing hormone (GnRH) likely require coordinated activity between GnRH neurons. We present our methodological approach for reliably obtaining simultaneous electrophysiological recordings from the diffusely distributed GnRH neurons.

双体录音从促性腺激素释放激素（GnRH）神经元下丘脑薄片鉴定绿色荧光蛋白（GFP）

Gonadotropin-Releasing Hormone (GnRH) is a small neuropeptide that regulates pituitary release of luteinizing hormone (LH) and follicle-stimulating ...

科研

神经科学

Calcium Imaging of Odor-evoked Responses in the Drosophila Antennal Lobe

The antennal lobe is the primary olfactory center in the insect brain and represents the anatomical and functional equivalent of the vertebrate olfactory bulb1-5. Olfactory information in the external world is transmitted to the antennal lobe by olfactory sensory neurons (OSNs), which segregate to distinct regions of neuropil called glomeruli according to the specific olfactory receptor they express. Here, OSN axons synapse with both local interneurons (LNs), whose processes can innervate many different glomeruli, and projection neurons (PNs), which convey olfactory information to higher olfactory brain regions.
Optical imaging of the activity of OSNs, LNs and PNs in the antennal lobe - traditionally using synthetic calcium indicators (e.g. calcium green, FURA-2) or voltage-sensitive dyes (e.g. RH414) - has long been an important technique to understand how olfactory stimuli are represented as spatial and temporal patterns of glomerular activity in many species of insects6-10. Development of genetically-encoded neural activity reporters, such as the fluorescent calcium indicators G-CaMP11,12 and Cameleon13, the bioluminescent calcium indicator GFP-aequorin14,15, or a reporter of synaptic transmission, synapto-pHluorin16 has made the olfactory system of the fruitfly, Drosophila melanogaster, particularly accessible to neurophysiological imaging, complementing its comprehensively-described molecular, electrophysiological and neuroanatomical properties2,4,17. These reporters can be selectively expressed via binary transcriptional control systems (e.g. GAL4/UAS18, LexA/LexAop19,20, Q system21) in defined populations of neurons within the olfactory circuitry to dissect with high spatial and temporal resolution how odor-evoked neural activity is represented, modulated and transformed22-24.
Here we describe the preparation and analysis methods to measure odor-evoked responses in the Drosophila antennal lobe using G-CaMP25-27. The animal preparation is minimally invasive and can be adapted to imaging using wide-field fluorescence, confocal and two-photon microscopes.

Calcium Imaging of Odor-evoked Responses in the Drosophila Antennal Lobe

We describe an established technique to measure and analyze odor-evoked calcium responses in the antennal lobe of living Drosophila melanogaster.

在气味诱发反应的钙成像果蝇触角叶

The antennal lobe is the primary olfactory center in the insect brain and represents the anatomical and functional equivalent of the vertebrate olfactory ...

Preparation of Acute Subventricular Zone Slices for Calcium Imaging

The subventricular zone (SVZ) is one of the two neurogenic zones in the postnatal brain. The SVZ contains densely packed cells, including neural progenitor cells with astrocytic features (called SVZ astrocytes), neuroblasts, and intermediate progenitor cells. Neuroblasts born in the SVZ tangentially migrate a great distance to the olfactory bulb, where they differentiate into interneurons. Intercellular signaling through adhesion molecules and diffusible signals play important roles in controlling neurogenesis. Many of these signals trigger intercellular calcium activity that transmits information inside and between cells. Calcium activity is thus reflective of the activity of extracellular signals and is an optimal way to understand functional intercellular signaling among SVZ cells.
Calcium activity has been studied in many other regions and cell types, including mature astrocytes and neurons. However, the traditional method to load cells with calcium indicator dye (i.e. bath loading) was not efficient at loading all SVZ cell types. Indeed, the cellular density in the SVZ precludes dye diffusion inside the tissue. In addition, preparing sagittal slices will better preserve the three-dimensional arrangement of SVZ cells, particularly the stream of neuroblast migration on the rostral-caudal axis.
Here, we describe methods to prepare sagittal sections containing the SVZ, the loading of SVZ cells with calcium indicator dye, and the acquisition of calcium activity with time-lapse movies. We used Fluo-4 AM dye for loading SVZ astrocytes using pressure application inside the tissue. Calcium activity was recorded using a scanning confocal microscope allowing a precise resolution for distinguishing individual cells. Our approach is applicable to other neurogenic zones including the adult hippocampal subgranular zone and embryonic neurogenic zones. In addition, other types of dyes can be applied using the described method.

A method to load subventricular zone (SVZ) cells with calcium indicator dyes for recording calcium activity is described. The postnatal SVZ contains tightly packed cells including neural progenitor cells and neuroblasts. Rather than using bath loading we injected the dye by pressure inside the tissue allowing better dye diffusion.

钙成像的急性下区片的制备

The subventricular zone (SVZ) is one of the two neurogenic zones in the postnatal brain. The SVZ contains densely packed cells, including neural ...

Two-photon Calcium Imaging in Neuronal Dendrites in Brain Slices

Calcium (Ca2+) imaging is a powerful tool to investigate the spatiotemporal dynamics of intracellular Ca2+ signals in neuronal dendrites. Ca2+ fluctuations can occur through a variety of membrane and intracellular mechanisms and play a crucial role in the induction of synaptic plasticity and regulation of dendritic excitability. Hence, the ability to record different types of Ca2+ signals in dendritic branches is valuable for groups studying how dendrites integrate information. The advent of two-photon microscopy has made such studies significantly easier by solving the problems inherent to imaging in live tissue, such as light scattering and photodamage. Moreover, through combination of conventional electrophysiological techniques with two-photon Ca2+ imaging, it is possible to investigate local Ca2+ fluctuations in neuronal dendrites in parallel with recordings of synaptic activity in soma. Here, we describe how to use this method to study the dynamics of local Ca2+ transients (CaTs) in dendrites of GABAergic inhibitory interneurons. The method can be also applied to studying dendritic Ca2+ signaling in different neuronal types in acute brain slices.

We present a method combining whole-cell patch-clamp recordings and two-photon imaging to record Ca2+ transients in neuronal dendrites in acute brain slices.

脑切片神经元树突的双光子钙成像

Calcium (Ca2+) imaging is a powerful tool to investigate the spatiotemporal dynamics of intracellular Ca2+ signals in neuronal dendrites. Ca2+ ...

Ratiometric Calcium Imaging of Individual Neurons in Behaving Caenorhabditis Elegans

It has become increasingly clear that neural circuit activity in behaving animals differs substantially from that seen in anesthetized or immobilized animals. Highly sensitive, genetically encoded fluorescent reporters of Ca2+ have revolutionized the recording of cell and synaptic activity using non-invasive optical approaches in behaving animals. When combined with genetic and optogenetic techniques, the molecular mechanisms that modulate cell and circuit activity during different behavior states can be identified.
Here we describe methods for ratiometric Ca2+ imaging of single neurons in freely behaving Caenorhabditis elegans worms. We demonstrate a simple mounting technique that gently overlays worms growing on a standard Nematode Growth Media (NGM) agar block with a glass coverslip, permitting animals to be recorded at high-resolution during unrestricted movement and behavior. With this technique, we use the sensitive Ca2+ reporter GCaMP5 to record changes in intracellular Ca2+ in the serotonergic Hermaphrodite Specific Neurons (HSNs) as they drive egg-laying behavior. By co-expressing mCherry, a Ca2+-insensitive fluorescent protein, we can track the position of the HSN within ~ 1 &#181;m and correct for fluctuations in fluorescence caused by changes in focus or movement. Simultaneous, infrared brightfield imaging allows for behavior recording and animal tracking using a motorized stage. By integrating these microscopic techniques and data streams, we can record Ca2+ activity in the C. elegans egg-laying circuit as it progresses between inactive and active behavior states over tens of minutes.

Ratiometric Calcium Imaging of Individual Neurons in Behaving Caenorhabditis Elegans

This protocol describes the use of genetically encoded Ca2+ reporters to record changes in neural activity in behaving Caenorhabditis elegans worms. &#8195;

比率钙显像对单个神经元的行为线虫线虫

It has become increasingly clear that neural circuit activity in behaving animals differs substantially from that seen in anesthetized or immobilized ...

Ex Vivo Calcium Imaging for Visualizing Brain Responses to Endocrine Signaling in Drosophila

Organ-to-organ communication by endocrine signaling, for example, from the periphery to the brain, is essential for maintaining homeostasis. As a model animal for endocrine research, Drosophila melanogaster, which has sophisticated genetic tools and genome information, is being increasingly used. This article describes a method for the calcium imaging of Drosophila brain explants. This method enables the detection of the direct signaling of a hormone to the brain. It is well known that many peptide hormones act through G-protein-coupled receptors (GPCRs), whose activation causes an increase in the intracellular Ca2+concentration. Neural activation also elevates intracellular Ca2+ levels, from both Ca2+ influx and the release of Ca2+ stored in the endoplasmic reticulum (ER). A calcium sensor, GCaMP, can monitor these Ca2+ changes. In this method, GCaMP is expressed in the neurons of interest, and the GCaMP-expressing larval brain is dissected and cultured ex vivo. The test peptide is then applied to the brain explant, and the fluorescent changes in GCaMP are detected using a spinning disc confocal microscope equipped with a CCD camera. Using this method, any water-soluble molecule can be tested, and various cellular events associated with neural activation can be imaged using the appropriate fluorescent indicators. Moreover, by modifying the imaging chamber, this method can be used to image other Drosophila organs or the organs of other animals.

Ex Vivo Calcium Imaging for Visualizing Brain Responses to Endocrine Signaling in Drosophila

This paper describes a protocol for ex vivo calcium imaging of the Drosophila brain. In this method, natural or synthetic compounds can be applied to the buffer to test their ability to activate particular neurons in the brain.

前体钙成像用于可视化大脑对果蝇内分泌信号的反应

Organ-to-organ communication by endocrine signaling, for example, from the periphery to the brain, is essential for maintaining homeostasis. As a model ...

Ballistic Labeling of Pyramidal Neurons in Brain Slices and in Primary Cell Culture

It has been reported that the size and shape of dendritic spines is related to their structural plasticity. To identify the morphological structure of pyramidal neurons and dendritic spines, a ballistic labeling technique can be utilized. In the present protocol, pyramidal neurons are labeled with DilC18(3) dye and analyzed using neuronal reconstruction software to assess neuronal morphology and dendritic spines. To investigate neuronal structure, dendritic branching analysis and Sholl analysis are performed, allowing researchers to draw inferences about dendritic branching complexity and neuronal arbor complexity, respectively. The evaluation of dendritic spines is conducted using an automatic assisted classification algorithm integral to the reconstruction software, which classifies spines into four categories (i.e., thin, mushroom, stubby, filopodia). Furthermore, an additional three parameters (i.e., length, head diameter, and volume) are also chosen to assess alterations in dendritic spine morphology. To validate the potential of wide application of the ballistic labeling technique, pyramidal neurons from in vitro cell culture were successfully labeled. Overall, the ballistic labeling method is unique and useful for visualizing neurons in different brain regions in rats, which in combination with sophisticated reconstruction software, allows researchers to elucidate the possible mechanisms underlying neurocognitive dysfunction.

We present a protocol to label and analyze pyramidal neurons, which is critical for evaluating potential morphological alterations in neurons and dendritic spines that may underlie neurochemical and behavioral abnormalities.

脑切片和原细胞培养中金字塔神经元的弹道标记

It has been reported that the size and shape of dendritic spines is related to their structural plasticity. To identify the morphological structure of ...

In vivo Calcium Imaging of Mouse Geniculate Ganglion Neuron Responses to Taste Stimuli

Within the last ten years, advances in genetically encoded calcium indicators (GECIs) have promoted a revolution in in vivo functional imaging. Using calcium as a proxy for neuronal activity, these techniques provide a way to monitor the responses of individual cells within large neuronal ensembles to a variety of stimuli in real time. We, and others, have applied these techniques to image the responses of individual geniculate ganglion neurons to taste stimuli applied to the tongues of live anesthetized mice. The geniculate ganglion is comprised of the cell bodies of gustatory neurons innervating the anterior tongue and palate as well as some somatosensory neurons innervating the pinna of the ear. Imaging the taste-evoked responses of individual geniculate ganglion neurons with GCaMP has provided important information about the tuning profiles of these neurons in wild-type mice as well as a way to detect peripheral taste miswiring phenotypes in genetically manipulated mice. Here we demonstrate the surgical procedure to expose the geniculate ganglion, GCaMP fluorescence image acquisition, initial steps for data analysis, and troubleshooting. This technique can be used with transgenically encoded GCaMP, or with AAV-mediated GCaMP expression, and can be modified to image particular genetic subsets of interest (i.e., Cre-mediated GCaMP expression). Overall, in vivo calcium imaging of geniculate ganglion neurons is a powerful technique for monitoring the activity of peripheral gustatory neurons and provides complementary information to more traditional whole-nerve chorda tympani recordings or taste behavior assays.

Here we present how to expose the geniculate ganglion of a live, anesthetized laboratory mouse and how to use calcium imaging to measure the responses of ensembles of these neurons to taste stimuli, allowing for multiple trials with different stimulants. This allows for in depth comparisons of which neurons respond to which tastants.

在活体钙成像小鼠致病性甘里昂神经元对味觉刺激的反应

Within the last ten years, advances in genetically encoded calcium indicators (GECIs) have promoted a revolution in in vivo functional imaging. Using ...

In vivo Calcium Imaging in Mouse Inferior Olive

Inferior olive (IO), a nucleus in the ventral medulla, is the only source of climbing fibers that form one of the two input pathways entering the cerebellum. IO has long been proposed to be crucial for motor control and its activity is currently considered to be at the center of many hypotheses of both motor and cognitive functions of the cerebellum. While its physiology and function have been relatively well studied on single-cell level in vitro, presently there are no reports on the organization of the IO network activity in living animals. This is largely due to the extremely challenging anatomical location of the IO, making it difficult to subject to conventional fluorescent imaging methods, where an optic path must be created through the entire brain located dorsally to the region of interest.
Here we describe an alternative method for obtaining state-of-the-art -level calcium imaging data from the IO network. The method takes advantage of the extreme ventral location of the IO and involves a surgical procedure for inserting a gradient-refractive index (GRIN) lens through the neck viscera to come into contact with the ventral surface of the calcium sensor GCaMP6s-expressing IO in anesthetized mice. A representative calcium imaging recording is shown to demonstrate the feasibility to record IO neuron activity after the surgery. While this is a non-survival surgery and the recordings must be conducted under anesthesia, it avoids damage to life-critical brainstem nuclei and allows conducting large variety of experiments investigating spatiotemporal activity patterns and input integration in the IO. This procedure with modifications could be used for recordings in other, adjacent regions of the ventral brainstem.

In vivo Calcium Imaging in Mouse Inferior Olive

We present a protocol to expose the brainstem of adult mouse from the ventral side. By using a gradient-refractive index lens with a miniature microscope, calcium imaging can be used to examine the activity of inferior olive neural somata in vivo.

在体内 小鼠劣质橄榄中的钙成像

Inferior olive (IO), a nucleus in the ventral medulla, is the only source of climbing fibers that form one of the two input pathways entering the ...

Detection of G Protein-coupled Receptor Expression in Mouse Vagal Afferent Neurons using Multiplex In Situ Hybridization

This study describes a protocol for the multiplex in situ hybridization (ISH) of the mouse jugular-nodose ganglia, with a particular emphasis on detecting the expression of G protein-coupled receptors (GPCRs). Formalin-fixed jugular-nodose ganglia were processed with the RNAscope technology to simultaneously detect the expression of two representative GPCRs (cholecystokinin and ghrelin receptors) in combination with one marker gene of either nodose (paired-like homeobox 2b, Phox2b) or jugular afferent neurons (PR domain zinc finger protein 12, Prdm12). Labeled ganglia were imaged using confocal microscopy to determine the distribution and expression patterns of the aforementioned transcripts. Briefly, Phox2b afferent neurons were found to abundantly express the cholecystokinin receptor (Cck1r) but not the ghrelin receptor (Ghsr). A small subset of Prdm12 afferent neurons was also found to express Ghsr and/or Cck1r. Potential technical caveats in the design, processing, and interpretation of multiplex ISH are discussed. The approach described in this article may help scientists in generating accurate maps of the transcriptional profiles of vagal afferent neurons.

Detection of G Protein-coupled Receptor Expression in Mouse Vagal Afferent Neurons using Multiplex In Situ Hybridization

Multiplex in situ hybridization (ISH) was employed to simultaneously visualize the transcripts for two G protein-coupled receptors and one transcription factor in the entire vagal ganglionic complex of the adult mouse. This protocol could be used to generate accurate maps of the transcriptional profiles of vagal afferent neurons.

使用多重 原位 杂交检测小鼠迷走神经传入神经元中G蛋白偶联受体表达

This study describes a protocol for the multiplex in situ hybridization (ISH) of the mouse jugular-nodose ganglia, with a particular emphasis on detecting ...