This study was supported in part by an Israel Science Foundation (ISF) grant (297/18). The authors thank M. Bronfeld for establishing the acute rodent model and M. Israelashvili for her comments.

<ol>
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C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+impact+of+a+stress+induction+task+on+tic+frequencies+in+youth+with+Tourette+Syndrome.">The impact of a stress induction task on tic frequencies in youth with Tourette Syndrome.</a> Behaviour Research and Therapy. 49 (8), 492-497 (2011).</li><li>Ganos, C., Rothwell, J., Haggard, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Voluntary+inhibitory+motor+control+over+involuntary+tic+movements.">Voluntary inhibitory motor control over involuntary tic movements.</a> Movement Disorders. 33 (6), 937-946 (2018).</li><li>Yael, D., Vinner, E., Bar-Gad, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pathophysiology+of+tic+disorders.">Pathophysiology of tic disorders.</a> Movement Disorders. 30 (9), 1171-1178 (2015).</li><li>Kurvits, L., Martino, D., Ganos, C., Eddy, C. 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W., Bronfeld, M., Belelovsky, K., Bar-Gad, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+neurophysiological+correlates+of+motor+tics+following+focal+striatal+disinhibition.">The neurophysiological correlates of motor tics following focal striatal disinhibition.</a> Brain. 132 (8), 2125-2138 (2009).</li><li>Worbe, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Behavioral+and+movement+disorders+induced+by+local+inhibitory+dysfunction+in+primate+striatum.">Behavioral and movement disorders induced by local inhibitory dysfunction in primate striatum.</a> Cerebral Cortex. 19 (8), 1844-1856 (2009).</li><li>Pogorelov, V., Xu, M., Smith, H. R., Buchanan, G. F., Pittenger, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Corticostriatal+interactions+in+the+generation+of+tic-like+behaviors+after+local+striatal+disinhibition.">Corticostriatal interactions in the generation of tic-like behaviors after local striatal disinhibition.</a> Experimental Neurology. 265, 122-128 (2015).</li><li>Bronfeld, M., Yael, D., Belelovsky, K., Bar-Gad, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Motor+tics+evoked+by+striatal+disinhibition+in+the+rat.">Motor tics evoked by striatal disinhibition in the rat.</a> Frontiers in Systems Neuroscience. 7, 50 (2013).</li><li>Vinner, E., Israelashvili, M., Bar-Gad, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prolonged+striatal+disinhibition+as+a+chronic+animal+model+of+tic+disorders.">Prolonged striatal disinhibition as a chronic animal model of tic disorders.</a> Journal of Neuroscience Methods. 292, 20-29 (2017).</li><li>Paxinos, G., Watson, C. <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 Rat Brain in Stereotaxic Coordinates. 6, (2007).</li><li>Flecknell, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analgesia+and+Post-Operative+Care.">Analgesia and Post-Operative Care.</a> Laboratory Animal Anaesthesia. , (2016).</li><li>Israelashvili, M., Bar-Gad, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Corticostriatal+divergent+function+in+determining+the+temporal+and+spatial+properties+of+motor+tics.">Corticostriatal divergent function in determining the temporal and spatial properties of motor tics.</a> Journal of Neuroscience. 35 (50), 16340-16351 (2015).</li><li>Bronfeld, M., Belelovsky, K., Bar-Gad, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spatial+and+temporal+properties+of+tic-related+neuronal+activity+in+the+cortico-basal+ganglia+loop.">Spatial and temporal properties of tic-related neuronal activity in the cortico-basal ganglia loop.</a> Journal of Neuroscience. 31 (24), 8713-8721 (2011).</li><li>McCairn, K. W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Primary+Role+for+Nucleus+Accumbens+and+Related+Limbic+Network+in+Vocal+Tics.">A Primary Role for Nucleus Accumbens and Related Limbic Network in Vocal Tics.</a> Neuron. 89 (2), 300-307 (2016).</li><li>Rizzo, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Aripiprazole+Selectively+Reduces+Motor+Tics+in+a+Young+Animal+Model+for+Tourette's+Syndrome+and+Comorbid+Attention+Deficit+and+Hyperactivity+Disorder.">Aripiprazole Selectively Reduces Motor Tics in a Young Animal Model for Tourette's Syndrome and Comorbid Attention Deficit and Hyperactivity Disorder.</a> Frontiers in Neurology. 9, 1-11 (2018).</li><li>Vinner, E., Matzner, A., Belelovsky, K., Bar-gad, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dissociation+of+tic+expression+from+its+neuronal+encoding+in+the+striatum+during+sleep.">Dissociation of tic expression from its neuronal encoding in the striatum during sleep.</a> bioRxiv. , (2020).</li><li>Webster, K. 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The authors have nothing to disclose.

In this manuscript, we detailed the protocols of the acute and chronic models for tic induction in a freely behaving rat. These protocols describe the preparation of all components, the surgery and the experimental process which can be adapted for customization to meet specific research needs. The primary principle underlying these models is the direct local application of bicuculline to the motor areas of the striatum, which is known to play a key role in the pathophysiology of tic disorders10<su...

Tics are the defining symptom of Tourette syndrome (TS) and other tic disorders. Tics are described as sudden, rapid, recurrent movements (motor tics), or vocalizations (vocal tics)1. Tic expression typically fluctuates in its temporal (frequency)2 and spatial (intensity, body location)3 properties over multiple time scales (hours, days, months, and years). These changes are affected by different factors, such as environmental features4,5, behavioral states6,7, and voluntary and temporary suppression8.
Although the neuronal mechanism governing motor tics is still not fully understood, an increasing number of theoretical and experimental studies have provided new evidence as to its nature9. Currently, the pathophysiology of tic generation is thought to involve the cortico-basal ganglia (CBG) loop, and specifically is associated with abnormal inhibition of the striatum, the primary basal ganglia input nucleus10,11,12. Previous studies in rodents and primates have demonstrated that the striatum can be disinhibited by local application of different GABAA antagonists, such as bicuculline and picrotoxin13,14,15,16,17,18. This pharmacological intervention leads to transient motor tic expression in the contralateral side to the injection, thus establishing a robust acute model of tic disorders with face and construct validity. The acute model is simple to induce and makes it possible to study the effects of short-term modulation such as electrical and optical stimulation concurrent with electrophysiological and kinematic recordings before, during and after tic expression. However, the acute model is limited to the short time period following the injection. Based on the acute model, we recently proposed a chronic model of tic generation in rats that utilizes a prolonged, fixed-rate infusion of bicuculline to the striatum via a subcutaneous-implanted mini-osmotic pump19. This model extends the period of tic expression to multiple days/weeks. The constant release of bicuculline over a lengthy period of time allows for the examination of the effects of a variety of factors such as pharmacological treatments and behavioral states on tic expression.
Here, we present protocols for generating the acute and chronic models of tic expression in rats. As a function of the specific research question, the protocols enable the fine-tuning of the parameters including unilateral versus bilateral implantation, the site of the tics (according to the somatotopic organization of the striatum)18 and the angle of the implant-cannula (depending on the location of additional implanted devices). The method used in the chronic model is partially based on commercial products but with critical adjustments to fit the tic model. This article details the adjustments needed to custom tailor these tic models.

<table><tbody><tr><td>Anchor screws</td><td>Micro Fasteners</td><td>SMPPS0002</td><td>#0 x 1/8 - Pan Head Sheet Metal Screws</td></tr><tr><td>Bicuculline methiodide</td><td>Sigma Aldrich</td><td>14343</td><td></td></tr><tr><td>Cyanoacrylate (CA) accelerator</td><td>Zap</td><td>PT29</td><td></td></tr><tr><td>Cyanoacrylate (CA) glue</td><td>BSI</td><td>IC-2000</td><td>This glue was found to be stronger than others</td></tr><tr><td>Dental cement</td><td>Coltene</td><td>H00322</td><td>Hygenic Perm Repair Material Reline Resin Self Cure</td></tr><tr><td>Glue gel</td><td>Loctite</td><td></td><td>Ultra Gel Control</td></tr><tr><td>Hemostat</td><td>WPI</td><td>501242</td><td>Any hemostat sized approximately 14 cm would be sufficient</td></tr><tr><td>Hypo-tube, extra-thin wall 25G</td><td>Component supply company</td><td>HTX-25X</td><td></td></tr><tr><td>Hypo-tube, regular wall 22G</td><td>Component supply company</td><td>HTX-22R</td><td></td></tr><tr><td>Hypo-tube, regular wall 30G</td><td>Component supply company</td><td>HTX-30R</td><td></td></tr><tr><td>Infusion pump machine</td><td>New Era Pump Systems</td><td>NE-1000</td><td></td></tr><tr><td>Mini-osmotic pump</td><td>ALZET</td><td>2001</td><td>1.0&amp;micro;l per hour, 7 days</td></tr><tr><td>PE compatible adhesive</td><td>CEYS</td><td></td><td>Special difficult plastics (suitable for PE)</td></tr><tr><td>PE-10 Catheter Tubing</td><td>ALZET</td><td>PE-10</td><td>ID = 0.28mm, OD = 0.61mm</td></tr><tr><td>Precision glass microsyringe, 10&amp;micro;l</td><td>Hamilton</td><td>80065</td><td>1701 RNR 10&amp;micro;l syr (22s/51/3)</td></tr><tr><td>Tissue adhesive</td><td>3M</td><td>1469Sb</td><td>Vetbond</td></tr><tr><td>Tubing-adapter</td><td>CMA</td><td>3409500</td><td></td></tr><tr><td>Tygon micro bore tubing, 0.02 inch ID * 0.06 OD</td><td>Component supply company</td><td>TND80-020</td><td></td></tr><tr><td>Wire 0.005-inch</td><td>Component supply company</td><td>GWX-0050</td><td></td></tr><tr><td>Wire 0.013-inch</td><td>Component supply company</td><td>GWX-0130</td><td></td></tr></tbody></table>

generating acute and chronic experimental models of motor tic expression in rats

Motor tics are sudden, rapid, recurrent movements that are the key symptoms of Tourette syndrome and other tic disorders. The pathophysiology of tic generation is associated with abnormal inhibition of the basal ganglia, particularly its primary input structure, the striatum. In animal models of both rodents and non-human primates, local application of GABAA antagonists, such as bicuculline and picrotoxin, into the motor parts of the striatum induces local disinhibition resulting in the expression of motor tics.
Here, we present acute and chronic models of motor tics in rats. In the acute model, bicuculline microinjections through a cannula implanted in the dorsal striatum elicit the expression of tics lasting for short time periods of up to an hour. The chronic model is an alternative enabling the extension of tic expression to periods of several days or even weeks, utilizing continuous infusion of bicuculline via a sub-cutaneous mini-osmotic pump.
The models enable the study of the behavioral and neural mechanisms of tic generation throughout the cortico-basal ganglia pathway. The models support the implantation of additional recording and stimulation devices in addition to the injection cannulas, thus allowing for a wide variety of usages such as electrical and optical stimulation and electrophysiological recordings. Each method has different advantages and shortcomings: the acute model enables the comparison of the kinematic properties of movement and the corresponding electrophysiological changes before, during and after tic expression and the effects of short-term modulators on tic expression. This acute model is simple to establish; however, it is limited to a short period of time. The chronic model, while more complex, makes feasible the study of tic dynamics and behavioral effects on tic expression over prolonged periods. Thus, the type of empirical query drives the choice between these two complementary models of tic expression.

Protocols for generating the acute and chronic models for tic induction in rats were presented above. The protocols cover the full preparation for surgery and experiments (Figure 1 for the acute model, Figure 2 for the chronic model). The application of bicuculline into the motor areas of the striatum results in the expression of ongoing motor tics. Tics appear on the contralateral side to the application and are characterized by brief and repetitive muscle cont...

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Generating Acute and Chronic Experimental Models of Motor Tic Expression in Rats

We present protocols for generating acute and chronic experimental models of tic expression in freely behaving rats. The models are based on striatal cannula implantation and subsequent GABAA antagonist application. The acute model uses transient injections whereas the chronic model utilizes prolonged infusions via a subcutaneous implanted mini-osmotic pump.

Motor tics are sudden, rapid, recurrent movements that are the key symptoms of Tourette syndrome and other tic disorders. The pathophysiology of tic ...

generating-acute-chronic-experimental-models-motor-tic-expression

Universidad de Cartagena UDEC

Research

JoVE Journal

Behavior

7.7K Views.  Bar-Ilan University. We present protocols for generating acute and chronic experimental models of tic expression in freely behaving rats. The models are based on striatal cannula implantation and subsequent GABAA antagonist application. The acute model uses transient injections whereas the chronic model utilizes prolonged infusions via a subcutaneous implanted mini-osmotic pump.

Video: Generating Acute and Chronic Experimental Models of Motor Tic Expression in Rats

Inchworming: A Novel Motor Stereotypy in the BTBR T+ Itpr3tf/J Mouse Model of Autism

Autism Spectrum Disorder (ASD) is a behaviorally defined neurodevelopmental disorder characterized by decreased reciprocal social interaction, abnormal communication, and repetitive behaviors with restricted interest. As diagnosis is based on clinical criteria, any potentially relevant rodent models of this heterogeneous disorder should ideally recapitulate these diverse behavioral traits. The BTBR T+ Itpr3tf/J (BTBR) mouse is an established animal model of ASD, displaying repetitive behaviors such as increased grooming, as well as cognitive inflexibility. With respect to social interaction and interest, the juvenile play test has been employed in multiple rodent models of ASD. Here, we show that when BTBR mice are tested in a juvenile social interaction enclosure containing sawdust bedding, they display a repetitive synchronous digging motion. This repetitive motor behavior, referred to as &#34;inchworming,&#34; was named because of the stereotypic nature of the movements exhibited by the mice while moving horizontally across the floor. Inchworming mice must use their fore- and hind-limbs in synchrony to displace the bedding, performing a minimum of one inward and one outward motion. Although both BTBR and C56BL/6J (B6) mice exhibit this behavior, BTBR mice demonstrate a significantly higher duration and frequency of inchworming and a decreased latency to initiate inchworming when placed in a bedded enclosure. We conclude that this newly described behavior provides a measure of a repetitive motor stereotypy that can be easily measured in animal models of ASD.

Inchworming: A Novel Motor Stereotypy in the BTBR T+ Itpr3tf/J Mouse Model of Autism

Inchworming is a highly repetitive synchronous digging motion displayed by BTBR T+ Itpr3tf/J (BTBR) mice when placed in a testing cage with sufficient sawdust bedding. The procedure is a modification of the juvenile social interaction protocol and is used here to assess repetitive motor stereotypies relevant to Autism Spectrum Disorder.

Autism Spectrum Disorder (ASD) is a behaviorally defined neurodevelopmental disorder characterized by decreased reciprocal social interaction, abnormal ...

Acquisition of a High-precision Skilled Forelimb Reaching Task in Rats

Movements are the main measurable output of central nervous system function. Developing behavioral paradigms that allow detailed analysis of motor learning and execution is of critical importance in order to understand the principles and processes that underlie motor function. Here we present a paradigm to study movement acquisition within a daily session of training (within-session) representing the fast learning component and primary acquisition as well as skilled motor learning over several training sessions (between-session) representing the slow learning component and consolidation of the learned task. This behavioral paradigm increases the degree of difficulty and complexity of the motor skill task due to two features: First, the animal realigns its body prior to each pellet retrieval forcing renewed orientation and preventing movement execution from the same angle. Second, pellets are grasped from a vertical post that matches the diameter of the pellet and is placed in front of the cage. This requires a precise grasp for successful pellet retrieval and thus prevents simple pulling of the pellet towards the animal. In combination with novel genetics, imaging and electrophysiological technologies, this behavioral method will aid to understand the morphological, anatomical and molecular underpinnings of motor learning and memory.

A paradigm is presented to analyze the acquisition of a high-precision skilled forelimb reaching task in rats.

Movements are the main measurable output of central nervous system function. Developing behavioral paradigms that allow detailed analysis of motor ...

A Novel Approach to Assess Motor Outcome of Deep Brain Stimulation Effects in the Hemiparkinsonian Rat: Staircase and Cylinder Test

Deep brain stimulation of the subthalamic nucleus is an effective treatment option for Parkinson&#39;s disease. In our lab we established a protocol to screen different neurostimulation patterns in hemiparkinsonian (unilateral lesioned) rats. It consists of creating a unilateral Parkinson&#39;s lesion by injecting 6-hydroxydopamine (6-OHDA) into the right medial forebrain bundle, implanting chronic stimulation electrodes into the subthalamic nucleus and evaluating motor outcomes at the end of 24 hr periods of cable-bound external neurostimulation. The stimulation was conducted with constant current stimulation. The amplitude was set 20% below the individual threshold for side effects. The motor outcome evaluation was done by the assessment of spontaneous paw use in the cylinder test according to Shallert and by the assessment of skilled reaching in the staircase test according to Montoya. This protocol describes in detail the training in the staircase box, the cylinder test, as well as the use of both in hemiparkinsonian rats. The use of both tests is necessary, because the staircase test seems to be more sensitive for fine motor skill impairment and exhibits greater sensitivity to change during neurostimulation. The combination of the unilateral Parkinson model and the two behavioral tests allows the assessment of different stimulation parameters in a standardized way.

Deep brain stimulation (DBS) is an effective treatment option for Parkinson's disease. We established a study design to screen novel stimulation paradigms in rats. The protocol describes the use of the staircase test and cylinder test for motor outcome assessment in DBS treated hemiparkinsonian rats.

Deep brain stimulation of the subthalamic nucleus is an effective treatment option for Parkinson&#39;s disease. In our lab we established a protocol to ...

Developing a Rat Model for Bipolar Disorder

Bipolar disorder is a mental health condition characterized by extreme mood swings, including periods of emotional highs (mania) and lows (depression). While the exact underlying neurobiology is not yet fully understood, imbalances in neurotransmitter systems, particularly dopamine, appear to play a central role. For this reason, manipulations of dopaminergic pathways have been used to model mania or depression in rodents. However, models that accurately represent the typical switch between these two episodes are rare, limiting face validity. In a unique model, modern techniques are used to temporarily increase dopamine D1 receptor expression, which has been implicated in the pathology of bipolar disorder. A tetracycline-inducible lentiviral construct that expresses the dopamine D1 receptor under the control of the calmodulin kinase II alpha promoter is stereotactically injected into the medial prefrontal cortex of adult rats. Dopamine D1 receptor overexpression is achieved by adding the tetracycline analog doxycycline to the animals&#39; drinking water, leading to an increase in reward-related, impulsive, and risk-taking behaviors and a decrease in anxiety. These behaviors resemble a mania-like phenotype. By removing doxycycline from the drinking water, a depressive-like phenotype, characterized by increased helplessness and anhedonia, can be induced within the same animal. This article provides a step-by-step protocol for performing the surgery, as well as procedures for inducing the bipolar disorder-like phenotype. Additionally, considerations for assessing behavioral changes associated with mania-like and depressive-like behavior are described. This promising model, which demonstrates good construct and face validity, offers a valuable tool for further investigating the pathophysiological mechanisms of bipolar disorder.

This article presents a protocol for the induction of a unique rat model of bipolar disorder that captures both mania-like and depressive-like behavior.

Bipolar disorder is a mental health condition characterized by extreme mood swings, including periods of emotional highs (mania) and lows (depression). ...

Motor and Hippocampal Dependent Spatial Learning and Reference Memory Assessment in a Transgenic Rat Model of Alzheimer's Disease with Stroke

Alzheimer&#39;s disease (AD) is a debilitating neurodegenerative disease that results in neurodegeneration and memory loss. While age is a major risk factor for AD, stroke has also been implicated as a risk factor and an exacerbating factor. The co-morbidity of stroke and AD results in worsened stroke-related motor control and AD-related cognitive deficits when compared to each condition alone. To model the combined condition of stroke and AD, a novel transgenic rat model of AD, with a mutated form of amyloid precursor protein (a key protein involved in the development of AD) incorporated into its DNA, is given a small unilateral striatal stroke.
For a model with the combination of both stroke and AD, behavioral tests that assess stroke-related motor control, locomotion and AD-related cognitive function must be implemented. The cylinder task involves a cost-efficient, multipurpose apparatus that assesses spontaneous forelimb motor use. In this task, a rat is placed in a cylindrical apparatus, where the rat will spontaneously rear and contact the wall of the cylinder with its forelimbs. These contacts are considered forelimb motor use and quantified during video analysis after testing. Another cost-efficient motor task implemented is the beam-walk task, which assesses forelimb control, hindlimb control and locomotion. This task involves a rat walking across a wooden beam allowing for the assessment of limb motor control through analysis of forelimb slips, hindlimb slips and falls. Assessment of learning and memory is completed with Morris water maze for this behavioral paradigm. The protocol starts with spatial learning, whereby the rat locates a stationary hidden platform. After spatial learning, the platform is removed and both short-term and long-term spatial reference memory is assessed. All three of these tasks are sensitive to behavioral differences and completed within 28 days for this model, making this paradigm time-efficient and cost-efficient.

To investigate the co-morbid Alzheimer&#39;s disease (AD) and stroke condition in a novel model, three behavior tasks are described that assess both motor control and cognitive behaviors. These tasks include the beam-walk task, cylinder task and Morris water maze.

Alzheimer&#39;s disease (AD) is a debilitating neurodegenerative disease that results in neurodegeneration and memory loss. While age is a major risk ...

Medicine

Rodent Behavioral Testing to Assess Functional Deficits Caused by Microelectrode Implantation in the Rat Motor Cortex

Medical devices implanted in the brain hold tremendous potential. As part of a Brain Machine Interface (BMI) system, intracortical microelectrodes demonstrate the ability to record action potentials from individual or small groups of neurons. Such recorded signals have successfully been used to allow patients to interface with or control&#160;computers, robotic limbs, and their own limbs. However, previous animal studies have shown that a microelectrode implantation in the brain not only damages the surrounding tissue but can also result in functional deficits. Here, we discuss a series of behavioral tests to quantify potential motor impairments following the implantation of intracortical microelectrodes into the motor cortex of a rat. The methods for open field grid, ladder crossing, and grip strength testing provide valuable information regarding the potential complications resulting from a microelectrode implantation. The results of the behavioral testing are correlated with endpoint histology, providing additional information on the pathological outcomes and impacts of this procedure on the adjacent tissue.

We have shown that a microelectrode implantation in the motor cortex of rats causes immediate and lasting motor deficits. The methods proposed herein outline a microelectrode implantation surgery and three rodent behavioral tasks to elucidate potential changes in the fine or gross motor function due to implantation-caused damage to the motor cortex.

Medical devices implanted in the brain hold tremendous potential. As part of a Brain Machine Interface (BMI) system, intracortical microelectrodes ...

Bioengineering

A Preclinical Model to Assess Brain Recovery After Acute Stroke in Rats

The purpose of this study was to establish and validate an animal brain ischemia model in the recovery and sequela stages. A middle cerebral artery occlusion/reperfusion (MCAO/R) model in male Sprague-Dawley rats was chosen. By changing the rat&#39;s weight (260&#8722;330 g), the thread bolt type (2636/2838/3040/3043) and the brain infarct time (2-3 h), a higher Longa&#39;s score, a larger infarct volume and a greater model success ratio were screened using the Longa&#39;s score and TTC staining. The optimum model condition (300 g, 3040 thread bolt, 3 h brain infarct time) was acquired and used in a 1-90 day observation period after reperfusion via assessment of sensorimotor functions and infarct volume. At these conditions, the bilateral asymmetry test had a significant difference from 1 to 90 days, and the grid-walking test had a significant difference from 1 to 60 days; both differences could be a suitable sensorimotor functional test. Thus, the most appropriate condition of a novel rat model in the recovery and sequela stages of brain ischemia was found: 300 g rats that underwent MCAO with a 3040 thread bolt for a 3 h brain infarct and then reperfused. The appropriate sensorimotor functional tests were a bilateral asymmetry test and a grid-walking test.

The&#160;purpose of this study is to establish and validate an animal model for research in the recovery and sequela stages of brain ischemia by testing brain infarction and sensorimotor function after middle cerebral artery occlusion/reperfusion (MCAO/R) after 1-90 days in rats.

The purpose of this study was to establish and validate an animal brain ischemia model in the recovery and sequela stages. A middle cerebral artery ...

Neuroscience

Establishment of Acute Pontine Infarction in Rats by Electrical Stimulation

Pontine infarction is the most common stroke subtype in the posterior circulation, while there lacks a rodent model mimicking pontine infarction. Provided here is a protocol for successfully establishing a rat model of acute pontine infarction. Rats weighing about 250 g are used, and a probe with an insulated sheath is injected into the pons using a stereotaxic apparatus. A lesion is produced by the electrical stimulation with a single pulse. The Longa score, Berderson score, and beam balance test are used to assess neurological deficits. Additionally, the adhesive-removal somatosensory test is used to determine sensorimotor function, and the limb placement test is used to evaluate proprioception. MRI scans are then used to assess the infarction in vivo, and TTC staining is used to confirm the infarction in vitro. Here, a successful infarction is identified that is located in the anterolateral basis of the rostral pons. In conclusion, a new method is described to establish an acute pontine infarction rat model.

Presented here is a protocol for establishing acute pontine infarction in a rat model via electrical stimulation with a single pulse.

Pontine infarction is the most common stroke subtype in the posterior circulation, while there lacks a rodent model mimicking pontine infarction. Provided ...

Multifactorial Assessment of Motor Behavior in Rats after Unilateral Sciatic Nerve Crush Injury

The induction of a peripheral nerve injury is a widely used method in neuroscience for the assessment of repair and pain mechanisms among others. In addition, in the research field of movement disorders, sciatic crush injury has been employed to trigger a dystonia-like phenotype in genetically predisposed DYT-TOR1A rodent models of dystonia. To achieve consistent, reproducible and comparable results after a sciatic nerve crush injury, a standardized method for inducing the nerve crush is essential, in addition to a standardized phenotypical characterization. Attention must be paid not only to the specific assortment of behavioral tests, but also to the technical requirements, the correct execution and consecutive data analysis. This protocol describes in detail how to perform a sciatic nerve crush injury and provides a behavioral test battery for the assessment of motor deficits in rats that includes the open field test, the CatWalk XT gait analysis, the beam walking task, and the ladder rung walking task.

We provide a protocol for the assessment of motor behavior via a behavioral test battery in rats after sciatic nerve crush injury.

The induction of a peripheral nerve injury is a widely used method in neuroscience for the assessment of repair and pain mechanisms among others. In ...

Assessing Motor Function in an Experimental Autoimmune Neuritis Mouse Model

Source: Gonsalvez, D. G., et al., <a href="https://appjove.unicartagenaproxy.elogim.com/v/56455">A Simple Approach to Induce Experimental Autoimmune Neuritis in C57BL/6 Mice for Functional and Neuropathological Assessments.</a> J. Vis. Exp. (2017).
This video demonstrates the process of assessing motor dysfunction in a mouse model through the administration of Pertussis toxin and an inoculum containing myelin-mimicking peptides and adjuvants, followed by treadmill tests to assess motor function and evaluate the resulting nerve damage due to immune activation and demyelination.

All procedures involving animal models have been reviewed by the local institutional animal care committee and the JoVE veterinary review board.
1. EAN ...