Live Cell Calcium Imaging Combined with siRNA Mediated Gene Silencing Identifies Ca2+ Leak Channels in the ER Membrane and their Regulatory Mechanisms
1Medical Biochemistry and Molecular Biology, Saarland University, 2Experimental and Clinical Pharmacology and Toxicology, Saarland University
The endoplasmic reticulum plays a key role in protein biogenesis and in calcium homeostasis. We have established an experimental system that allows us to address the role of Ca2+ leak channels and to characterize their putative regulatory mechanisms. This system involves siRNA mediated gene silencing and live cell Ca2+ imaging.
Primary Culture of Hippocampal Neurons from P0 Newborn Rats
Department of Psychology, Michigan State University (MSU)
The dissection and growth of cells from an individual brain area facilitates investigation of cellular and physiological parameters. We describe a method for primary cell culturing that produces neuron-enriched cultures in a serum-free environment.
Imaging Pheromone Sensing in a Mouse Vomeronasal Acute Tissue Slice Preparation
1Department of Pharmacology and Toxicology, University of Lausanne, 2Department of Genetics and Evolution, University of Geneva
In mice, the ability to detect pheromones is principally mediated by the vomeronasal organ (VNO). Here, an acute tissue slice preparation of VNO for performing calcium imaging is described. This physiological approach allows observations of subpopulations and/or individual neurons in a living tissue and is convenient for receptor-ligand identification.
Calcium Imaging of Cortical Neurons using Fura-2 AM
1Department of Neurobiology, Stanford University, 2Department of Neurobiology, Stanford University School of Medicine
Calcium signals play a key role in many cellular processes including gene expression, survival and differentiation. Here we demonstrate how to perform calcium imaging using Fura-2 AM. Calcium imaging is a valuable tool to study the regulation of intracellular calcium in real time and its regulation of signaling cascades.
Dissection, Culture, and Analysis of Xenopus laevis Embryonic Retinal Tissue
Department of Biology, College of William and Mary
Xenopus laevis provides an ideal model system for studying cell fate specification and physiological function of individual retinal cells in primary cell culture. Here we present a technique for dissecting retinal tissues and generating primary cell cultures that are imaged for calcium activity and analyzed by in situ hybridization.
In Vivo 2-Photon Calcium Imaging in Layer 2/3 of Mice
Department of Neurology, University of California, Los Angeles
To understand network dynamics of microcircuits in the neocortex, it is essential to simultaneously record the activity of a large number of neurons . In-vivo two-photon calcium imaging is the only method that allows one to record the activity of a dense neuronal population with single-cell resolution .
Optical Recording of Suprathreshold Neural Activity with Single-cell and Single-spike Resolution
Section of Neurobiology, Center for Learning and Memory, The University of Texas at Austin
Understanding the function of the vertebrate central nervous system requires recordings from many neurons because cortical function arises on the level of populations of neurons. Here we describe an optical method to record suprathreshold neural activity with single-cell and single-spike resolution, dithered random-access scanning. This method records somatic fluorescence calcium signals from up to 100 neurons with high temporal resolution. A maximum-likelihood algorithm deconvolves the underlying suprathreshold neural activity from the somatic fluorescence calcium signals. This method reliably detects spikes with high detection efficiency and a low rate of false positives and can be used to study neural populations in vitro and in vivo.
Measuring Fast Calcium Fluxes in Cardiomyocytes
1Department of Biological Sciences and Geology, Queensborough Community College, 2Department of Physiology & Biophysics, Stony Brook University
We present a method to isolate rapid (microsecond) calcium events from slower fluxes in living cells using laser scanning confocal microscopy. The method measures fluorescence intensity fluctuations of calcium indicators by recording line scans of several hundred pixels in a cell. Histogram analysis allows us to isolate the time scales of different calcium fluxes.
Monitoring Changes in the Intracellular Calcium Concentration and Synaptic Efficacy in the Mollusc Aplysia
1Fishberg Department of Neuroscience and Friedman Brain Institute, Mt. Sinai School of Medicine, 2Phase Five Communications Inc.
We demonstrate how changes in the intracellular free calcium concentration and synaptic efficacy can be simultaneously monitored in a ganglion preparation of Aplysia. We image intracellular calcium using a fluorescent dye, Calcium Orange, and induce and monitor synaptic transmission with sharp (intracellular) electrodes.
Monitoring Dynamic Changes In Mitochondrial Calcium Levels During Apoptosis Using A Genetically Encoded Calcium Sensor
Department of Neuroscience and Cell Biology, University of Texas Medical Branch
This protocol describes a method for real-time measurement of mitochondrial calcium fluxes by fluorescent imaging. The method takes advantage of a circularly permutated YFP-based dual-excitation ratiometric calcium sensor (ratiometric pericam-mt) selectively expressed in mitochondria.
Dual Electrophysiological Recordings of Synaptically-evoked Astroglial and Neuronal Responses in Acute Hippocampal Slices
1Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, CNRS UMR 7241, INSERM U1050, Collège de France, 2Paris Diderot University
The preparation of acute brain slices from isolated hippocampi, as well as the simultaneous electrophysiological recordings of astrocytes and neurons in stratum radiatum during stimulation of schaffer collaterals is described. The pharmacological isolation of astroglial potassium and glutamate transporter currents is demonstrated.
Direct Imaging of ER Calcium with Targeted-Esterase Induced Dye Loading (TED)
1Institute for Clinical Neurobiology, University of Wuerzburg, 2Department of Synapses - Circuits - Plasticity, Max Planck Institute of Neurobiology, Martinsried, 3Walter Brendel Centre of Experimental Medicine, Ludwig-Maximilians University of Munich
Targeted-esterase induced dye loading (TED) supports the analysis of intracellular calcium store dynamics by fluorescence imaging. The method bases on targeting of a recombinant Carboxylesterase to the endoplasmic reticulum (ER), where it improves the local unmasking of synthetic low-affinity Ca2+ indicator dyes in the ER lumen.
An Isolated Semi-intact Preparation of the Mouse Vestibular Sensory Epithelium for Electrophysiology and High-resolution Two-photon Microscopy
1Discipline of Biomedical Science, School of Medical Sciences, Sydney Medical School, University of Sydney, 2School of Biomedical Sciences and Pharmacy, University of Newcastle
Analysis of vestibular hair cell function is complicated by their location deep within the hardest part of the skull, the petrous temporal bone. Most functional hair cell studies have used acutely isolated hair cells. Here we describe a semi-intact preparation of mouse vestibular epithelium for electrophysiological and two-photon microscopy studies.
Vibrodissociation of Neurons from Rodent Brain Slices to Study Synaptic Transmission and Image Presynaptic Terminals
1Section on Synaptic Pharmacology/Laboratory for Integrative Neuroscience, National Institutes of Health/National Institute on Alcohol Abuse and Alcoholism, 2Department of Electronics Engineering, Ewha Womans University, 3Section on Transmitter Signaling/Laboratory of Molecular Physiology, National Institutes of Health/National Institute on Alcohol Abuse and Alcoholism
This report demonstrates a technique for mechanical isolation of individual viable neurons retaining attached presynaptic boutons. Vibrodissociated neurons have the advantages of rapid production, excellent pharmacological control and improved space-clamp without influence from neighboring cells. This method can be used for imaging of synaptic elements and patch-clamp recording.
Functional Calcium Imaging in Developing Cortical Networks
Department of Integrative Neurophysiology, VU University, Amsterdam
Spontaneous activity of developing neuronal networks can be measured using AM-ester forms of calcium-sensitive indicator dyes. Changes in intracellular calcium, indicating neuronal activation, are detected as transient changes in indicator fluorescence with one- or two-photon imaging. This protocol can be adapted for a range of developmentally-dependent neuronal networks in vitro.
March 2012: This Month in JoVE
Here are some highlights from the March 2012 Issue of Journal of Visualized Experiments (JoVE).
In vivo Ca2+- Imaging of Mushroom Body Neurons During Olfactory Learning in the Honey Bee
1Institut für Biologie - Neurobiologie, Freie Universität Berlin, 2Institut für Biologie - Neurobiologie, Free University Berlin - Freie Universitaet Berlin
Bees can be conditioned in an appetitive olfactory learning paradigm (PER-conditioning). Using odors as stimuli, we established a method in which behavior is recorded while simultaneously Calcium Imaging is used to measure odor evoked activity in mushroom body neurons in vivo.
In Vivo Two-photon Imaging Of Experience-dependent Molecular Changes In Cortical Neurons
1Unit on Neural Circuits and Adaptive Behaviors, Genes Cognition and Psychosis Program, National Institute of Mental Health, 2Department of Neuroscience, Brown University - National Institutes of Health Graduate Partnership Program, 3Section on Synaptic Pharmacology, Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, 4Champalimaud Neuroscience Programme, Champalimaud Center for the Unknown
Experience-dependent molecular changes in neurons are essential for the brain's ability to adapt in response to behavioral challenges. An in vivo two-photon imaging method is described here that allows the tracking of such molecular changes in individual cortical neurons through genetically encoded reporters.
Preparation of Acute Subventricular Zone Slices for Calcium Imaging
Department of Neurosurgery and Cellular & Molecular Physiology, Yale University School of Medicine
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.
In vivo Neuronal Calcium Imaging in C. elegans
1Department of Physiology and Biophysics, Boston University School of Medicine, 2Boston University Photonics Center
With its small transparent body, well-documented neuroanatomy and a host of amenable genetic techniques and reagents, C. elegans makes an ideal model organism for in vivo neuronal imaging using relatively simple, low-cost techniques. Here we describe single neuron imaging within intact adult animals using genetically encoded fluorescent calcium indicators.
Primary Neuronal Cultures from the Brains of Late Stage Drosophila Pupae
This video demonstrates the preparation of primary neuronal cultures from the brains of late stage Drosophila pupae. Views of live cultures show neurite outgrowth and imaging of calcium levels using Fura-2.
September 2011: This Month in JoVE
Here are some highlights from the September 2011 Issue of Journal of Visualized Experiments (JoVE).
Multi-unit Recording Methods to Characterize Neural Activity in the Locust (Schistocerca Americana) Olfactory Circuits
Department of Biomedical Engineering, Washington University in St. Louis
We demonstrate variations of the extracellular multi-unit recording technique to characterize odor-evoked responses in the first three stages of the invertebrate olfactory pathway. These techniques can easily be adapted to examine ensemble activity in other neural systems as well.
Measuring Near Plasma Membrane and Global Intracellular Calcium Dynamics in Astrocytes
We describe how to measure near membrane and global intracellular calcium dynamics in cultured astrocytes using total internal reflection and epifluorescence microscopy.
Optical Mapping of Action Potentials and Calcium Transients in the Mouse Heart
Department of Biomedical Engineering, Washington University in St. Louis
This paper details the dissection procedure, instrumental setup, and experimental conditions during optical mapping of transmembrane potential (Vm) and intracellular calcium transient (CaT) in intact isolated Langendorff perfused mouse hearts.
December 2011: This Month in JoVE
Here are some highlights from the December 2011 Issue of Journal of Visualized Experiments (JoVE).
Horizontal Slice Preparation of the Retina
1Dpt of Physiology and Biophysics, Dalhousie University, 2Massachusetts General Hospital, Harvard Medical School
Traditionally the vertical slice and the whole-mount preparation of the retina have been used to study the function of retinal circuits. Here, we describe the novel slicing method to preserve the dendritic morphology of retinal neurons intact.
Technique to Collect Fungiform (Taste) Papillae from Human Tongue
1Department of Basic Science and Craniofacial Biology, College of Dentistry, New York University, 2Department of Internal Medicine and Department of Psychiatry, School of Medicine, Washington University in St. Louis, 3Veterans Affairs Medical Center, 4School of Dental Medicine, Department of Biochemistry, University of Pennsylvania-School of Medicine, 5 , Monell Chemical Senses Center, 6Monell Chemical Senses Center
Knowledge of molecular mechanisms underlying gustatory transduction has recently enjoyed significant advances, largely due to using animal models. However, the wide diversity in taste sensitivity and specificity among mammals warrants studies in human tissue. We describe a biopsy technique to collect living taste cells from the papillae on human tongue.
Isolation and Kv Channel Recordings in Murine Atrial and Ventricular Cardiomyocytes
1Experimental and Clinical Research Center (ECRC), Charité Medical Faculty and Max-Delbrück Center for Molecular Medicine (MDC), 2Medical Department, Division of Cardiology, Campus Virchow-Klinikum, Charité - Universitätsmedizin Berlin, 3Medical Department, Division of Cardiology and Angiology, Campus Mitte, Charité - Universitätsmedizin Berlin
Kv channel dysfunction is associated with cardiac arrhythmias. In order to study the molecular mechanisms that lead to such arrhythmias we utilize a systematic protocol for isolation of atrial and ventricular cardiomyocytes from Kv channel ancillary subunit knockout mice. Isolated cardiomyocytes can then immediately be used for cellular electrophysiological studies, biochemical or immunofluorescence (IF) assays.
Simultaneous Recording of Calcium Signals from Identified Neurons and Feeding Behavior of Drosophila melanogaster
Department of Neurobiology, University of Massachusetts Medical School
The fruit fly, Drosophila melanogaster, extends its proboscis for feeding, responding to a sugar stimulus from its proboscis or tarsus. I have combined observations of the proboscis extension response (PER) with a calcium imaging technique, allowing us to monitor the activity of neurons in the brain, simultaneously with behavioral observation.
Voltage-sensitive Dye Recording from Axons, Dendrites and Dendritic Spines of Individual Neurons in Brain Slices
Department of Cellular and Molecular Physiology, Yale University School of Medicine
An imaging technique for monitoring of membrane potential changes with sub-micrometer spatial and sub-millisecond temporal resolution is described. The technique, based on laser excitation of voltage-sensitive dyes, allows measurements of signals in axons and axon collaterals, terminal dendritic branches, and individual dendritic spines.
Implementing Dynamic Clamp with Synaptic and Artificial Conductances in Mouse Retinal Ganglion Cells
1Discipline of Biomedical Science, School of Medical Sciences, Sydney Medical School and Bosch Institute, University of Sydney, 2The MARCS Institute, University of Western Sydney, 3Discipline of Physiology, School of Medical Sciences, Sydney Medical School and Bosch Institute, University of Sydney
This video article illustrates the set-up, the procedures to patch cell bodies and how to implement dynamic clamp recordings from ganglion cells in whole-mount mouse retinae. This technique allows the investigation of the precise contribution of excitatory and inhibitory synaptic inputs, and their relative magnitude and timing to neuronal spiking.
Isolation and Genetic Manipulation of Adult Cardiac Myocytes for Confocal Imaging
Institute for Molecular Cell Biology, Universty of Saarland
Adult cardiac myocytes are primary cells that can be isolated from animal hearts and cultured for several days. Within this culture period adenoviral gene transfer can be used to express genetically encoded biosensors (GEBs) or fluorescent fusion proteins. Both approaches allow cellular investigations by means of confocal microscopy.
Calcium Imaging of Odor-evoked Responses in the Drosophila Antennal Lobe
1Center for Integrative Genomics, University of Lausanne, 2Department of Biology, University of Konstanz
We describe an established technique to measure and analyze odor-evoked calcium responses in the antennal lobe of living Drosophila melanogaster.
Imaging Neuronal Responses in Slice Preparations of Vomeronasal Organ Expressing a Genetically Encoded Calcium Sensor
1Stowers Institute for Medical Research, 2Department of Anatomy and Cell Biology, The University of Kansas School of Medicine
The vomeronasal organ (VNO) detects intraspecies chemical signals that convey social and reproductive information. We have performed Ca2+ imaging experiments using transgenic mice expressing G-CaMP2 in VNO tissue. This approach allows us to analyze the complicated response patterns of the vomeronasal neurons to large numbers of pheromone stimuli.
Isolation and Culture of Human Fungiform Taste Papillae Cells
1Monell Chemical Senses Center, 2New York University College of Dentistry, 3AFB International
We aimed to develop a reproducible protocol for isolating and maintaining long-term cultures of human fungiform taste papillae cells. Cells from human fungiform papillae obtained by biopsy were successfully maintained in culture for more than eight passages (12 months) without loss of viability.
Patch-clamp Capacitance Measurements and Ca2+ Imaging at Single Nerve Terminals in Retinal Slices
The Vollum Institute, Oregon Health and Science University
Here we describe a protocol for the preparation of agar-embedded retinal slices that are suitable for electrophysiology and Ca2+ imaging. This method allows one to study ribbon-type synapses in retinal microcircuits using direct patch-clamp recordings of single presynaptic nerve terminals.
Imaging Calcium Responses in GFP-tagged Neurons of Hypothalamic Mouse Brain Slices
Department of Physiology, School of Medicine, University of Saarland, Homburg, Germany
In this protocol, we update recent progress in imaging Ca2+ signals of GFP-tagged neurons in brain tissue slices using a red fluorescent Ca2+ indicator dye.
DiI-Labeling of DRG Neurons to Study Axonal Branching in a Whole Mount Preparation of Mouse Embryonic Spinal Cord
Developmental Neurobiology, Max Delbrück Center for Molecular Medicine
The stereotyped projections of sensory afferents into the rodent spinal cord offer an easily accessible experimental system to study axonal branching through the tracing of single axons.
Selective Tracing of Auditory Fibers in the Avian Embryonic Vestibulocochlear Nerve
Department of Neurobiology and Behavior, University of California, Irvine
Here we describe a microdissection technique followed by fluorescent dye injection into the acoustic ganglion of early chick embryos for selective tracing of auditory axon fibers in the nerve and hindbrain.
Targeted Labeling of Neurons in a Specific Functional Micro-domain of the Neocortex by Combining Intrinsic Signal and Two-photon Imaging
Department of Neuroscience, Medical University of South Carolina
A method is described for labeling neurons with fluorescent dyes in predetermined functional micro-domains of the neocortex. First, intrinsic signal optical imaging is used to obtain a functional map. Then two-photon microscopy is used to label and image neurons within a micro-domain of the map.
A Polished and Reinforced Thinned-skull Window for Long-term Imaging of the Mouse Brain
1Department of Physics, University of California, San Diego, 2Department of Engineering Science and Mechanics, Pennsylvania State University, 3Department of Neurosurgery, Pennsylvania State University, 4Section of Neurobiology, University of California, San Diego
We present a method to form an imaging window in the mouse skull that spans millimeters and is stable for months without inflammation of the brain. This method is well suited for longitudinal studies of blood flow, cellular dynamics, and cell/vascular structure using two-photon microscopy.
Bilaminar Co-culture of Primary Rat Cortical Neurons and Glia
Department of Pharmacology and Physiology, Drexel University College of Medicine
Here we provide a protocol for culturing rat cortical neurons in the presence of a glial feeder layer. The cultured neurons establish polarity and create synapses, and can be separated from the glia for use in various applications, such as electrophysiology, calcium imaging, cell survival assays, immunocytochemistry, and RNA/DNA/protein isolation.
Multiparametric Optical Mapping of the Langendorff-perfused Rabbit Heart
Department of Biomedical Engineering, Washington University in St. Louis
This article describes the basic procedures for conducting optical mapping experiments in the Langendorff-perfused rabbit heart using the panoramic imaging system, and the dual (voltage and calcium) imaging modality.
Preparation of Parasagittal Slices for the Investigation of Dorsal-ventral Organization of the Rodent Medial Entorhinal Cortex
1Neuroinformatics DTC, University of Edinburgh, 2Centre for Integrative Physiology, University of Edinburgh
We describe procedures for preparation and electrophysiological recording from brain slices that maintain the dorsal-ventral axis of the medial entorhinal cortex (MEC). Because neural encoding of location follows a dorsal-ventral organization within the MEC, these procedures facilitate investigation of cellular mechanisms important for navigation and memory.
Visualization of Bacterial Toxin Induced Responses Using Live Cell Fluorescence Microscopy
1Department of Immunology, University of Pittsburgh School of Medicine, 2Department of Cell Biology and Physiology, University of Pittsburgh School of Medicine
Methods for purifying the cholesterol binding toxin streptolysin O from recombinant E. coli and visualization of toxin binding to live eukaryotic cells are described. Localized delivery of toxin induces rapid and complex changes in targeted cells revealing novel aspects of toxin biology.
In vitro Labeling of Human Embryonic Stem Cells for Magnetic Resonance Imaging
Division of Cardiovascular Medicine, Stanford University
In this video, we are showing how to label human embryonic stem cells (hESC) with manganese chloride (MnCl2) which can enter cells via voltage-gated calcium channels when the cells are biologically active. Additionally, we show the use of MnCl2 as cellular MRI contrast agent to determine the in vitro viability of hESC.
Intranuclear Microinjection of DNA into Dissociated Adult Mammalian Neurons
Direct intranuclear injection of cDNA is an effective transfection technique for post-mitotic cells. This method provides high levels of heterologous protein expression from single or multiple cDNA constructs and enables protein function to be studied in a physiologically relevant environment with a variety of single cell assays.
Quantification of Atherosclerotic Plaque Activity and Vascular Inflammation using [18-F] Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (FDG-PET/CT)
1Division of Cardiovascular Medicine, University of Pennsylvania, Perelman School of Medicine, 2Department of Radiology, University of Pennsylvania, Perelman School of Medicine, 3Department of Dermatology, University of Pennsylvania, Perelman School of Medicine
There is great need to identify atherosclerosis non-invasively, and here we demonstrate how FDG-PET/CT can be used to detect and quantify atherosclerotic plaque activity and vascular inflammation.
Single-Molecule Imaging of Nuclear Transport
1Department of Biology, Bowling Green State University, 2Center for Photochemical Sciences, Bowling Green State University
Single molecule microscopy approch provided novel insights into nuclear transport.
