Scientific Tools

Mouse Genetics and Lentiviruses

We are manipulating both the levels and the site of expression of different stress-related neuropeptides and receptors, within key CNS regions, and studying the specific neuronal circuits mediating their effects by analyzing their neuroendocrine and behavioral stress-related phenotypes and biochemical neuroanatomy tools. We are designing and generating transgenic mice models, lentiviruses and combined models, for site-specific knockdown/knockout or over-expression of stress-related neuropeptides and receptors.

Grip Strengh System

The Grip Strength system (TSE-systems) assesses the gripping strength of mice as an indicator of neuromuscular functions; This system is used to quantify the effects of hormones, toxins, muscle relaxants as well as diseases or the aging process that affect neuromuscular or muscular functions. In a test trial a mouse pulls a special height-adjustable grip which is connected to a high-precision force sensor (up to 600 pounds).

Gene Regulation and Molecular Mechanisms

We are studying the regulation of stress-related neuropeptides and receptors at the protein, mRNA and promoter levels. We explore the molecular mechanisms of central stress-related neuropeptides and receptors, express in distinct brain nuclei, by identifying downstream genes and pathways. We dissect specific brain nuclei from different mice models or following specific stress-related paradigm and determine the gene expression and microRNA profiles using microarray technology and bioinformatics analysis. Confirmation of candidate genes or microRNAs, using Real-Time PCR, in-situ hybridization, immunohistochemistry or western blot, is followed by in vivo functional analysis using mouse genetics and/or direct siRNA-lentiviral approach.

Gene Regulation and Molecular Mechanisms

We are studying the regulation of stress-related neuropeptides and receptors at the protein, mRNA and promoter levels. We explore the molecular mechanisms of central stress-related neuropeptides and receptors, express in distinct brain nuclei, by identifying downstream genes and pathways. We dissect specific brain nuclei from different mice models or following specific stress-related paradigm and determine the gene expression and microRNA profiles using microarray technology and bioinformatics analysis. Confirmation of candidate genes or microRNAs, using Real-Time PCR, in-situ hybridization, immunohistochemistry or western blot, is followed by in vivo functional analysis using mouse genetics and/or direct siRNA-lentiviral approach.

Computerized Treadmill System

The Treadmill system (TSE-systems) is a fully computerized electronically-controlled system that is used to assess exercise physiology in mice. A servo-controlled motor provides precise operator-defined speed profiles, 0.07 to 2m/sec, that may be set as either constant speed or acceleration/deceleration phases with adjustable durations; furthermore, the inclination angle may be adjusted (-10 to + 25 degrees). This system is set up to connect to the calorimetric system, PhenoMaster (TSE-systems) allowing the assessment of metabolic parameters.

Elevated plus maze (EPM)

The Elevated plus maze is a Plexiglas apparatus containing two open arms and two enclosed arms of the same size with walls. The arms are connected by a central square and thus the maze forms a plus sign. It is elevated above the ground. The height and exposed atmosphere, as experienced on the open arms tests the level of anxiety of the animal. Exploration on the open arms is reduced in high anxiety states while it is increased in low anxiety states. The number of entries into and the time spent on the open arms as well as the overall percentage of the open arm entries compared with total number of arm entries are measured.

The Mouse CatWalk

The CatWalk system (Noldus) is used for quantita­tive assessment of footfalls and gait in mouse models of neurotrauma, neurodegeneration, neurological diseases, or pain symptoms. It has been validated in research on spinal cord injury, neuropathic pain, arthritis, stroke, Parkinson’s, ataxia, brain traumatic injury, and peripheral nerve damage. The system consists of an enclosed walkway that is traversed by a mouse from one side of the walkway to the other side. Thanks to the Illuminated Footprints technology, real footprints are captured by a high speed video camera that is positioned underneath the walkway. The video capture is processed based on the dimensions, position, dynamics and pressure of each footfall to produce several parameters that are calculated for qualitative and quantitative analyses of footfalls and gait including: CatWalk XT automatically calculates parameters, including: stance, brake, propulsion, and swing phase; duty cycle; pressure; stand index; cadence; stride length; base of support; step sequence; phase lags; support formulas; regularity index and more.

Telemetry System

The telemetry system (DSI) allows the recording of physiological parameters like ECG, EMG, EEG, EOG, respiration, temperature, activity. The system is comprised of subcutaneous implanted sensors that transmit information to receivers located under the mice cages which in turn relay the information to a data recording and analyses software. This system allows the monitoring and collecting data from conscious, freely moving mice providing stress-free data collection while eliminating pericutaneous infections.

Stereotaxic Injection Systems

The “Benchmark Angle Two Stereotaxic Instrument” (myNeuroLab.com) is a computer-guided, small animal stereotaxic system with 5 axes encoders. The 3 linear axes and rotation and tilt of the manipulator are all computer guided. This allows full integration of stereotaxic brain injection with a digital brain atlas. The user may scroll the atlas plates on the computer screen, and click on the desired target point to set the target coordinates. Following placing the mice in the head-rest, the user may tilt and rotate the probe holder to any complex angle of approach, while the computer displays the distance along each linear axis to the selected target, follows the syringe movement and guide the user to the desired target.

LabMaster

The LabMaster system (TSE-systems) is a modular system for automated metabolic and behavioral monitoring of small laboratory animals. The LabMaster instrument consists of a combination of highly sensitive feeding and drinking sensors for automated online measurement. For food preference experiments four sensors are allocated per cage. The calorimetry system is an open-circuit system that determines O2 consumption, CO2 production, and RER (repertory exchange ratio). Spontaneous home cage activity is monitored using photobeam-based activity system that detects and records every movement, including rearing and climbing movements, in every cage. The sensors for detection of movement operate efficiently in both light and dark phases, allowing continuous recording. All the parameters can be measured continuously and simultaneously.

VideoMot

The TSE VideoMot2 is a Multi-purpose videotracking system suitable for a large variety of behavioral paradigms such as Open-Field, Dark-Light Transfer, Morris Water Maze, Novel Object Recognition, Plus Maze and other mazes (T,Y, 8-arms etc). The software allows easy analysis of the tests data such as walked distances, time spent in different areas of the arena and rearing.

Open-Field Test

This test measures activity in a novel environment and can be used to assess a combination of locomotor activity, exploratory drive, neophobia, agoraphobia and other aspects of anxiety or fear in mice, as well as motor function. Testing sessions typically last up to 10 min. The apparatus consists of a Plexiglas arena (50×50 cm; 44 cm high). The mice's activity is monitored by the TSE VideoMot2 video tracking system. Quantitative parameters, such as the distance traveled and average speed, are recorded for the center zone of the arena and the entire arena. The more the mouse explores the arena, particularly its center, the less it is considered anxious.

Light/Dark Transfer Test

This test takes advantage of the natural conflict of a rodent between the exploration of a novel environment and the aversive properties of a large, brightly lit open field. The test apparatus is a rectangular Plexiglas box divided by a partition into two environments. One compartment is dark, and the other compartment is brightly illuminated. The compartments are connected by an opening located at the floor level in the center of the partition. The more a mouse spends light compartment and the more transitions it makes the less it is considered anxious. Elevated plus maze (EPM) This test is assesses anxiety, based on mice preference for dark, enclosed places over bright, exposed ones. This maze (TSE systems) consists of two open arms and two enclosed (high-walled) arms of the same size. All four arms are connected to a central square and thus it resembles a "PLUS" (+) form which is elevated above the ground. Typically a mouse is placed in the center of the apparatus and observed for 5 min. The mice's activity is monitored by the TSE VideoMot2 video tracking system. Quantitative parameters, such as the time spent in the open arms, and distance traveled, are recorded. The more the mouse explores the maze, particularly the open arms, the less it is considered anxious.

Tail suspension

This test assesses depressive-like behaviors in mice, both for basic research studies and in antidepressant screening. This apparatus (TSE systems) automatically monitors movements, and reports mobility and immobility time throughout the test session. During this test the animal is being suspended from its tail for several minutes, in which it may try to escape the aversive situation, or remain immobile. Immobility behavior is considered an index of helplessness or behavioral despair (lack of motivation). The longer time the mouse is immobile during the test, the more its behavior is considered depressive-like.

Acoustic startle reflex/response (ASR)

The acoustic startle reflex (ASR) is a well characterized response to an abrupt loud sound. It is common across species including rodents and humans. In rodents it is manifested by contractions of the major body muscles. An enhanced startle response is a hallmark of increased fear and/or sustained anxiety and is especially common among patients who suffer from anxiety disorders like generalized anxiety (GAD) or post-traumatic stress disorder (PTSD). The Startle Response System is used in our lab to compare this response between different lines of transgenic mice and between mice which were exposed to different environmental conditions that may affect the function of the limbic system.

Morris water maze

This maze tests the formation of hippocampal-dependant spatial memories. In the typical paradigm, a mouse is placed into a pool of water where an escape platform hidden a few millimeters below the water surface is located. Visual cues, such as distinct shapes, are placed around the pool in plain sight of the mouse. When released, the mouse swims around the pool in search of an exit while various parameters are recorded (latency to reach the platform; total distance traveled and the time spent in each quadrant of the pool). The mouse's escape from the water reinforces it to quickly find the platform, and on subsequent trials (with the platform in the same position) the mouse locates the platform more rapidly because the mouse learns where the hidden platform is located relative to those distinct visual cues. After enough practice, an able mouse swims directly to the platform from any release point. The Morris water maze is used in our lab to compare spatial memory faculties between different lines of transgenic mice and between mice that were exposed to different environmental conditions that may affect the function of the hippocampus.

Fear Conditioning

The fear conditioning system (TSE-systems) monitors for the mice innate freezing response to potential harm (lack of movement except for respiration and heartbeats), and assesses learning and memory of aversive events. This task allows for simultaneously assessing learning about a simple (unimodal) cue, typically a tone, and learning about complex (multimodal) stimuli such as the context. Associating fear with the cue (the conditioned stimulus; CS) depends on the integrity of the amygdala, while context conditioning is sensitive to manipulations of the hippocampus. In a typical procedure, training (conditioning) consists of two pairings of tone (CS) and an aversive foot-shock (the unconditioned stimulus; US); contextual memory is tested in the same context as the training, but no CS or US are presented; while the cue memory test is performed in a novel context where the CS is presented. The duration of the freezing behavior serves as an index of the memories' strength, i.e. the more time a mouse spends freezing the stronger is its association of the US with either stimuli. This task is used in our lab to compare memory faculties between different lines of transgenic mice and between mice that were exposed to different manipulation or environmental conditions that may have affected the function of either the amygdala or the hippocampus.

InfraMot

The TSE InfraMot is a home-cage based movement-quantifying system. The InfraMot unit registers activity by sensing the body-heat image, i.e. infra-red radiation, and its spatial displacement over time. The information allows studying the locomotor activity of the animals for several days: before, after and even during testing.

Environmental Enrichment Cages

Environmental enrichment (EE) refers to housing conditions that facilitate, sensory, cognitive, motor and social stimulation relative to standard housing conditions that severely restricts natural behavior and the animal's control over its environment. EE has beneficial neurobiological, physiological and behavioral effects. Evidence supports the view that EE attenuates stress responses, protects from excessive anxiety in the face of new challenges (such as stress induced by novel stimuli or restraint), reverses the effect of past stressors, and causes a general reduction in emotionality measures.

Optogenetics

Halorhodopsin (NpHR) and Channelrhodopsin-2 (ChR2) are recombinant light-gated ion transporters for chloride ions or cations, respectively. Each channel is selectively activated by different wavelength of light. These channels can be used for the precise control over neuronal activation or inhibition in genetically altered neuronal cells. This genetic based technique offers an exciting opportunity for the study of the neural substrates of behavior. By genetically manipulating certain cell types or brain structures to express these channels, one could potentially switch on or off, reversibly and in a precisely controlled manner, certain neural circuits in the mouse brain while it is engaged in a task. We are Implementing a method for the effective delivery of wavelength specific light to neurons by stereotactically implanting a cannula through which an optic fiber connected to a laser light source is inserted to reach specific brain structures.