A demonstration of the isolation of neonatal mouse spinal cord for electrophysiologic studies.
A demonstration of the fabrication and use of an extracellular suction electrode used to measure electrophysiological recordings of neonatal rodent spinal cords in vitro
Simultaneous Intracellular Recording of a Lumbar Motoneuron and the Force Produced by its Motor Unit in the Adult Mouse In vivo
This new method permits the simultaneous intracellular recording of a single adult mouse motoneuron and the measurement of the force produced by its muscle fibers. The combined investigation of the electrical and mechanical properties of motor units in normal and genetically modified animals is a breakthrough for the study of the neuromuscular system.
1Norton Neuroscience Institute, Norton Healthcare, 2Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery and Goodman and Campbell Brain and Spine, Medical Neuroscience Graduate Program, and Department of Anatomy and Cell Biology, Indiana University School of Medicine
A novel technique to create a reproducible in vivo model of cervical spinal cord laceration injury in the mouse is described. This technique is based on spine stabilization by fixation of the cervical facets and laceration of the spinal cord using an oscillating blade with an accuracy of ±0.01 mm.
Kinematics and Ground Reaction Force Determination: A Demonstration Quantifying Locomotor Abilities of Young Adult, Middle-aged, and Geriatric Rats
1CullenWebb Animal Neurology & Ophthalmology Center, Riverview, NB, 2Department of Clinical Neurosciences, Faculty of Medicine, University of Calgary, 3Department of Comparative Biology and Experimental Medicine, University of Calgary, 4Department of Neuroscience, University of Calgary
Locomotion is often examined as a behavioural outcome in various models of disease in fields such as neuroscience and orthopedics. This video paper intends to describe a method for collecting ground reaction forces and kinematics from rats during unrestrained locomotion.
The study of complex locomotor behavior in Drosophila melanogaster is dependent upon the ability to quantify changes in a given fly's movement. This article demonstrates how to do this using a high-resolution tracking system.
An injury paradigm using the Drosophila larval ventral nerve cord to investigate central nervous system regeneration and repair is described. Stabbing followed by laser scanning confocal microscopy in time-lapse and fixed specimens, combined with quantitative analysis with purposefully developed software and genetics, are used to investigate the molecular mechanisms of CNS regeneration and repair.
We have developed a video-rate tracking microscope system that can record and quantify C. elegans behavior at high resolution and high speeds. We have also developed computational methods to reduce the dimensionality of the worm images to a fundamental set of measurements that completely describe the shape of the worm.
Microfluidic-based Electrotaxis for On-demand Quantitative Analysis of Caenorhabditis elegans' Locomotion
A semi-automated micro-electro-fluidic method to induce on-demand locomotion in Caenorhabditis elegans is described. This method is based on the neurophysiologic phenomenon of worms responding to mild electric fields (“electrotaxis”) inside microfluidic channels. Microfluidic electrotaxis serves as a rapid, sensitive, low-cost, and scalable technique to screen for factors affecting neuronal health.
T lymphocyte migration occurs during homing to lymphoid organs, exit from the vasculature, and entering into peripheral tissues. Here, we describe a protocol that can be used to analyze T lymphocyte migration in vitro.
A technique is described to quantify the in vivo physiological response of mammalian neurons during movement and correlate the physiology of the neuron with neuronal morphology, neurochemical phenotype and synaptic microcircuitry.
Microscopic organisms like the free-swimming nematode C. elegans, live and behave in a complex three-dimensional environment. We report on a novel approach that provides analysis of C. elegans using diffraction patterns. This approach consists of tracking the temporal periodicity of diffraction patterns generated by directing laser light through a cuvette.
In this video-article we present a method for the isolation and purification of Drosophila peripheral neurons using a fast magnetic bead assisted cell sorting strategy. RNA obtained from the isolated cells can be readily used for downstream applications including microarray analyses.
RNAi Mediated Gene Knockdown and Transgenesis by Microinjection in the Necromenic Nematode Pristionchus pacificus
In model organisms, transgenesis can manipulate gene functions while RNAi can knockdown specific mRNA transcripts 1-2. This protocol aims to illustrate the techniques needed to introduce stably transmitted DNA and transient double stranded RNA into the necromenic nematode Pristionchus pacificus for studies in evolutionary, developmental, and behavioral biology.
Drosophila melanogaster is a genetically and behaviorally tractable model system that has been used to understand the molecular and cellular basis of many important biological processes for over a century 1. Drosophila has been well exploited to gain insights into the genetic basis of fly behavior.
Morphological Analysis of Drosophila Larval Peripheral Sensory Neuron Dendrites and Axons Using Genetic Mosaics
The dendritic arborization sensory neurons of the Drosophila larval peripheral nervous system are useful models to elucidate both general and neuron class-specific mechanisms of neuron differentiation. We present a practical guide to generate and analyze dendritic arborization neuron genetic mosaics.
The ladder rung walking task is a new test to assess skilled walking and measure both forelimb and hindlimb placing, stepping, and inter-limb co-ordination.
We describe a simple and low cost technique for introducing high concentration of fluorescent and calcium-sensitive dyes into neurons or any neuronal tract using a polyethylene suction pipette.
Evaluation of Cancer Stem Cell Migration Using Compartmentalizing Microfluidic Devices and Live Cell Imaging
1Department of Biomedical Engineering, University of Wisconsin-Madison, 2Materials Science Program, University of Wisconsin-Madison, 3Department of Neurological Surgery, University of Wisconsin-Madison, 4Carbone Comprehensive Cancer Center and Center for Stem Cell and Regenerative Medicine, University of Wisconsin-Madison
A compartmentalizing microfluidic device for investigating cancer stem cell migration is described. This novel platform creates a viable cellular microenvironment and enables microscopic visualization of live cell locomotion. Highly motile cancer cells are isolated to study molecular mechanisms of aggressive infiltration, potentially leading to more effective future therapies.
Cutaneous Leishmaniasis in the Dorsal Skin of Hamsters: a Useful Model for the Screening of Antileishmanial Drugs
Optimization of the experimental hamster model for cutaneous leishmaniasis by intradermal injection of Leishmania promastigotes at the dorsal skin. This approach is useful during inoculation, follow-up, characterization of lesions, application of treatments and obtaining of clinical samples. Locomotion, search for food and water, play and social activities are preserved.
In this paper, we describe a useful method to study ligand-gated ion channel function in neurons of acutely isolated brain slices. This method involves the use of a drug-filled micropipette for local application of drugs to neurons recorded using standard patch clamp techniques.
1Department of Biochemistry and Molecular Biology, The University of Texas MD Anderson Cancer Center, 2Scholars Academy/MARC Scholar, University of Houston-Downtown, 3Genes and Development Graduate Program, University of Texas Graduate School of Biomedical Sciences, 4Neuroscience Graduate Program, University of Texas Graduate School of Biomedical Sciences
In this article, we demonstrate assays to study thermal nociception in Drosophila larvae. One assay involves spatially-restricted (local) stimulation of thermal nociceptors1,2 while the second involves a wholesale (global) activation of most or all such neurons3. Together, these techniques allow visualization and quantification of the behavioral functions of Drosophila nociceptive sensory neurons.
1Department of Biochemistry, University of Washington, 2Department of Neurology, University of Washington, 3Division of Genetics, Departments of Pediatrics and Cellular and Molecular Medicine, and the Institute for Genomic Medicine, University of California, San Diego - Rady Children’s Hospital
We describe a protocol for the rapid and sensitive quantification of disease severity in mouse models of cerebellar ataxia. Measures include hind limb clasping, ledge test, gait and kyphosis. This protocol effectively discriminates between affected and non-affected individuals, and detects the progression of affected individuals over time.
Supported planar bilayers are powerful tools that can be used to model the molecular interactions in an immunological synapse. Here, we show methods for anchoring cell adhesion proteins known to modulate synapse formation to the upper leaflet of the lipid bilyer and visualize synapse formation using TIRF microscopy.
Neutrophils are among the first cells to arrive on the site of inflammatory immune response, and their functions and mechanisms have been studied extensively in vitro. We demonstrate a standard density gradient separation method to isolate human neutrophils from whole blood using commercially available separation media.
Surgical Transplantation of Mouse Neural Stem Cells into the Spinal Cords of Mice Infected with Neurotropic Mouse Hepatitis Virus
1Department of Molecular Biology and Biochemistry, University of California, Irvine, 2Sue and Bill Gross Stem Cell Center, University of California, Irvine, 3Institute for Immunology, University of California, Irvine
The transplantation of mouse neural stem cells (NSCs) into the spinal cords of mice with established demyelination is detailed. The preparation of NSCs, the laminectomy of thoracic vertebra 9 (T9), and transplantation of NSCs is outlined along with the pre- and post-operative care of the mice.
The methodology for fabricating synthetic vocal fold models is described. The models are life-sized and mimic the multi-layer structure of the human vocal folds. Results show the models to self-oscillate at pressures comparable to lung pressure and demonstrate flow-induced vibratory responses that are similar to those of human vocal folds.
A simple microfluidic device has been developed to perform anesthetic free in vivo imaging of C. elegans, intact Drosophila larvae and zebrafish larvae. The device utilizes a deformable PDMS membrane to immobilize these model organisms in order to perform time lapse imaging of numerous processes such as heart beat, cell division and sub-cellular neuronal transport. We demonstrate the use of this device and show examples of different types of data collected from different model systems.
The mouse model of cecal ligation and puncture as a valuable tool for the study of human sepsis.
The rotorod test is used to assess motor status in the walking movement of hemi-Parkinson analogue rats.
1Sensory Motor Performance Program, Rehabilitation Institute of Chicago, 2Department of Kinesiology and Nutrition, University of Illinois at Chicago, 3Department of Physical Therapy, University of Illinois at Chicago
This video demonstrates modulation of reflex activity, volitional strength and ambulation through clinical and quantitative assessments in individuals with motor incomplete SCI as a result of acute oral administration of a serotonin reuptake inhibitor (SSRI).
Voice disorders are debilitating in aging and Parkinson disease. The ultrasonic vocalizations of rats, also affected by these conditions, can be used to study these voice disorders, their neural substrates, and the nature of functional recovery with behavioral intervention.
Filamentous occlusion of the Middle cerebral artery is a common model for studying ischemic stroke in mice.
Here are some highlights from the December 2011 Issue of Journal of Visualized Experiments (JoVE).
Tracking Neutrophil Intraluminal Crawling, Transendothelial Migration and Chemotaxis in Tissue by Intravital Video Microscopy
We describe a protocol of brightfield intravital microscopy for measuring dynamic neutrophil-endothelial cell interactions during neutrophil recruitment in response to the source of a neutrophil chemoattractant in vivo. Neutrophil intraluminal crawling, transendothelial migration and chemotaxis in mouse cremaster muscle tissue are visualized with time-lapsed video photography and tracked with ImageJ.
An alternative way of isolating mouse embryonic motoneurons from the spinal cord is described. The method takes into account the fact that lectin can bind to the low affinity nerve growth factor receptor p75NTR. This lectin-based preplating allows a purification similar to that with a specific antibody against the p75NTR.
The effect of substrata stiffness on cellular function can be modeled in vitro using polyacrylamide hydrogels of varying compliances.
A protocol for isolating and activating spermatids from male C. elegans is described here. Cutting the posterior end of male releases spermatids. The spermatids can be activated by addition of protease.
The primary purpose of this experiment is to understand how primary sensory neurons convey information of joint movements and positions as proprioceptive information for an animal. An additional objective of this report is present the anatomy of the preparation by dissection and viewing of neurons under a dissecting microscope.
A simple assay to measure the sedating effects of ethanol on Drosophila flies, based on the loss of righting reflex, is described.
1Department of Medicine, Weill Cornell Medical College, 2Department of Oral Biology, University of Missouri-Kansas City-School of Dentistry, 3Department of Pharmacology and Toxicology, University of Missouri Kansas City- School of Pharmacy, 4Regional Hospital, Bamenda, NWP, Cameroon, 5Mezam Polyclinic HIV/AIDS Treatment Center, Cameroon, 6Institute for Human Genetics and Biochemistry
A CD4 enumeration method, the α-test, is described which uses whole saliva to provide rapid and accurate CD4 counts. The α-test costs pennies and eliminates the need for technical training, costly reagents such as monoclonal antibodies, instrumentation, refrigeration, transport of samples, as well as collection and handling of blood.
Behavior assays for measuring locomotor functions, learning, and memory abilities in Drosophila.
Mice and rats, due to their innate cautiousness, are initially slow in consuming a novel food, particularly in a novel place. This hyponeophagia can readily be measured in the laboratory, even though laboratory animals are much less anxious than their wild counterparts
Fundamental, yet unique properties of the rodent olfactory system have led to its increasing study among biologists. A relatively simple assessment of its function is then also needed. Here we describe sensitive tests for the characterization of mouse olfactory sensitivity and preference.
This video demonstrates how to employ two neural stimulants, aldicarb and pentylenetetrazole (PTZ), in complementary ways to study synaptic function in the nematode, C. elegans. This complementary approach may also be used to shed light on evolutionarily conserved mechanisms for modulating neuronal synchrony and has implications for epilepsy and seizures.
Application of electrophysiology to accessible synapses provides a quantifiable measure of synaptic activity, useful in analyzing synaptic mutants. This article describes a dissection method used to expose the neuromuscular junctions (NMJ) of Caenorhabditis elegans (C. elegans) and briefly discusses some of the uses to which this preparation can be applied.
Here we describe an efficient strategy to remove the silk-producing glands from the abdomen of female black widow spiders. This procedure allows the rapid isolation of the seven distinct silk-producing glands in a highly purified fashion, an important process for investigators studying spider silk production and fiber assembly.
A Fully Automated and Highly Versatile System for Testing Multi-cognitive Functions and Recording Neuronal Activities in Rodents
In this report, we present a fully automated and highly versatile system capable of simultaneously testing multi-cognitive behaviors and recording neuronal activities for rodents.
A method for developing cell culture substrates with the ability to change topography during culture is described. The method makes use of smart materials known as shape memory polymers that have the ability to memorize a permanent shape. This concept is adaptable to a wide range of materials and applications.
Time lapse imaging of 3D tissue culture allows studying migratory behavior of individual cells originating from ganglionic eminence in reaction to fractionated protein extract from cerebral cortex.