This work was supported by funding from the Indiana Spinal Cord &#38; Brain Injury Research Grants (SCBI 200-12), the Ralph W. and Grace M. Showalter Research Award, Indiana University Biological Research Grant, NIH grants RR025761 and 1R21NS072631-01A.

Animal Care 
Male C57 BL/6 mice were group-housed and kept in a 12/12 hr light/dark cycle with free to access to food and water ad libitum. The animals used in this protocol were 10-12 weeks old. All procedures were performed under protocols approved by Indiana University&#8217;s Animal Care and Use Committee.
1. Surgical Preparation
<ol>
	<li>Anesthetize the mouse using a Ketamine/xylazine&#160;mixture (87.7 mg/ml Ketamine and 12.3 mg/ml Xylazine)&#160;and administer&#160;(1 ml/kg) via IP injection.</li>
	<li>Shave the head of the mouse between the ears.</li>
	<li>Apply a petroleum-based jelly&#160;to the eyes of the mouse to prevent drying out during surgery.</li>
	<li>Clean the shaven area with 10% iodine. Then use 70% ethanol to clean off the iodine.</li>
	<li>Fix the mouse head in the stereotactic frame using the ear bars and bite plate. Ensure the brain is stable.</li>
</ol>
2. Craniectomy
<ol>
	<li>Make a longitudinal incision in the middle of the head with scissors. Use a hemostat to hold skin off to the left side.</li>
	<li>Use a cotton-tipped applicator to remove the blood and tissue on the bone to expose the skull. Allow exposed skull to dry for 1 min.</li>
	<li>Use forceps to apply pressure and ensure that the skull remains immobile. Identify anatomical landmarks Lambda (caudal aspect) and Bregma (frontal aspect). Draw a circle in the center of Lambda and Bregma with a 4&#160;mm diameter and 0.5&#160;mm away from the midline.</li>
	<li>Use a drill to cut along the marked circle. Gently blow bone dust away. Do not drill completely through the bone to prevent damaging the dura mater.</li>
	<li>Use forceps to remove bone and expose the dura mater.</li>
</ol>
3. Impaction
The impact system includes a control box to set impact parameters, an actuator to perform the impaction, and a stereotactic frame to secure the actuator and mouse head for impact.
<ol>
	<li>Pre-set the velocity of the actuator to 3&#160;m/sec before surgery.</li>
	<li>Pre-set different deformation depth to induce different injury severities. Deformation depths of 0.0-0.2 mm, 0.5-1.0 mm, and 1.2-2.0 mm would result in mild, moderate, and severe TBIs, respectively. This protocol explained how to achieve a moderately severe brain injury with a deformation depth of 1&#160;mm by using a velocity of 3&#160;m/sec.</li>
	<li>Attach the actuator to the holder in the stereotactic frame and use the micromanipulators moving it to secure the round, flat tip of the actuator (3&#160;mm diameter) in the center of the open skull area. Then adjust the tip at an angle parallel to the surface of impact site.</li>
	<li>Establish the zero point by moving down the actuator in the extending model until the tip touches the surface of the impact site. Then set the Z channel on the stereotactic control panel to zero.</li>
	<li>Retract the impactor tip while simultaneously moving the actuator down 1&#160;mm.</li>
	<li>Hit the impact button to strike the injury site and achieve a deformation depth of 1&#160;mm.</li>
</ol>
4. Injury Site Closure
<ol>
	<li>Use cotton-tipped applicators to remove any blood following impact, but do not touch the injury area.</li>
	<li>Place mouse on a warm pad to maintain body temperature.</li>
	<li>Once bleeding has stopped, suture the wound closed. Put the animal back into the clean cage and allow it to recover from the surgery overnight on the warm pad.</li>
	<li>Administer&#160;Buprenorphine 0.05-0.10 mg/kg SQ every 8-12 hr&#160;for 2 days after surgery.</li>
</ol>

<ol>
	<li>Menon, D. K., Schwab, K., 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=Position+statement:+definition+of+traumatic+brain+injury.">Position statement: definition of traumatic brain injury.</a> Arch Phys Med Rehabil. 91 (11), 1637-1640 (2010).</li><li>Lighthall, J. W., Dixon, C. E., 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=Experimental+models+of+brain+injury.">Experimental models of brain injury.</a> J Neurotrauma. 6 (2), 83-97 (1989).</li><li>Dixon, C. E., Clfton, G. L., 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+controlled+cortical+impact+model+of+traumatic+brain+injury+in+the+rat.">A controlled cortical impact model of traumatic brain injury in the rat.</a> J Neurosci Methods. 39 (3), 253-262 (1991).</li><li>Scheff, S. W., Baldwin, S. A., 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=Morris+water+maze+deficits+in+rats+following+traumatic+brain+injury:+lateral+controlled+cortical+impact.">Morris water maze deficits in rats following traumatic brain injury: lateral controlled cortical impact.</a> J Neurotrauma. 14 (9), 615-627 (1997).</li><li>Smith, D. H., Soares, H. D., 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+model+of+parasagittal+controlled+cortical+impact+in+the+mouse:+cognitive+and+histopathologic+effects.">A model of parasagittal controlled cortical impact in the mouse: cognitive and histopathologic effects.</a> J Neurotrauma. 12 (2), 169-178 (1995).</li><li>Hannay, H. J., Feldman, Z., 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=Validation+of+a+controlled+cortical+impact+model+of+head+injury+in+mice.">Validation of a controlled cortical impact model of head injury in mice.</a> J Neurotrauma. 16 (11), 1103-1114 (1999).</li><li>Natale, J. E., Ahmed, 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=Gene+expression+profile+changes+are+commonly+modulated+across+models+and+species+after+traumatic+brain+injury.">Gene expression profile changes are commonly modulated across models and species after traumatic brain injury.</a> J Neurotrauma. 20 (10), 907-927 (2003).</li><li>Anderson, R. W., Brown, C. J., 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=Impact+mechanics+and+axonal+injury+in+a+sheep+model.">Impact mechanics and axonal injury in a sheep model.</a> J Neurotrauma. 20 (10), 961-974 (2003).</li><li>Lighthall, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Controlled+cortical+impact:+a+new+experimental+brain+injury+model.">Controlled cortical impact: a new experimental brain injury model.</a> J Neurotrauma. 5 (1), 1-15 (1988).</li><li>Chen, S., Pickard, J. D., 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=Time+course+of+cellular+pathology+after+controlled+cortical+impact+injury.">Time course of cellular pathology after controlled cortical impact injury.</a> Exp Neurol. 182 (1), 87-102 (2003).</li><li>Long, J. B., Bentley, T. L., 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=Blast+overpressure+in+rats:+recreating+a+battlefield+injury+in+the+laboratory.">Blast overpressure in rats: recreating a battlefield injury in the laboratory.</a> J Neurotrauma. 26 (6), 827-840 (2009).</li><li>Clark, R. S., Schiding, J. K., 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=Neutrophil+accumulation+after+traumatic+brain+injury+in+rats:+comparison+of+weight+drop+and+controlled+cortical+impact+models.">Neutrophil accumulation after traumatic brain injury in rats: comparison of weight drop and controlled cortical impact models.</a> J Neurotrauma. 11 (5), 499-506 (1994).</li><li>Werner, C., Engelhard, K. <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+traumatic+brain+injury.">Pathophysiology of traumatic brain injury.</a> Br J Anaesth. 99 (1), 4-9 (2007).</li><li>Colicos, M. A., Dixon, C. E., 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=Delayed,+selective+neuronal+death+following+experimental+cortical+impact+injury+in+rats:+possible+role+in+memory+deficits.">Delayed, selective neuronal death following experimental cortical impact injury in rats: possible role in memory deficits.</a> Brain Res. 739 (1-2), 111-119 (1996).</li><li>Raghavendra Rao, V. L., Dogan, A., 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=Traumatic+brain+injury+leads+to+increased+expression+of+peripheral-type+benzodiazepine+receptors,+neuronal+death,+and+activation+of+astrocytes+and+microglia+in+rat+thalamus.">Traumatic brain injury leads to increased expression of peripheral-type benzodiazepine receptors, neuronal death, and activation of astrocytes and microglia in rat thalamus.</a> Exp Neurol. 161 (1), 102-114 (2000).</li><li>Gao, X., Chen, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Moderate+traumatic+brain+injury+promotes+neural+precursor+proliferation+without+increasing+neurogenesis+in+the+adult+hippocampus.">Moderate traumatic brain injury promotes neural precursor proliferation without increasing neurogenesis in the adult hippocampus.</a> Exp Neurol. 239, 38-48 (2013).</li></ol>

The authors have nothing to disclose.

The most critical steps for successfully generating consistent TBIs using an electronic magnet impact system to cause a CCI are: 1) stably fixing the mouse head in the stereotactic frame; 2) generating the same size of bone window between mice and removing the bone without damaging the dura under it during craniectomy; 3) correctly positioning the impact tip in the center of the open area and establishing the zero point before impacting.
A mouse head must be fixed in the stereotactic frame ver...

Traumatic brain injury (TBI) is defined as an alteration in brain function, or other evidence of brain pathology, caused by an external force1. TBIs remain a serious health problem throughout the world, particularly in the United States. According to the Centers for Disease Control and Prevention, at least 1.7 million TBIs occur annually in the United States resulting in 30.5% of all injury-related deaths. In 2000, the direct medical costs and indirect costs of TBIs totaled an estimated $76.5 billion in the United States alone. Although technological and therapeutic advancements in preceding decades have improved the quality and length of life for those suffering from TBIs, no effective pharmaceutical or preventative treatments currently exist. Due to the complexity and wide-reaching effects of TBIs, including tissue lesions, cell death, and axon degeneration, no two injuries are identical; thus, no current TBI model for animals accurately reproduces all aspects of TBI as seen in humans. However, animal models do provide the ability to produce nearly identical injuries necessary to investigate various effects of TBI with the hope of further understanding the clinical manifestations of TBIs.
The controlled cortical impact (CCI) model uses an impact system to deliver physical impact to the exposed dura of an animal. It induces TBIs ranging from mild to severe similar to those experienced by humans. This injury was first characterized in the ferret2 and was later adapted for use in the rat3,4, mouse5-7, and sheep8. Since the first characterization, the site of injury has been placed both over the midline2,9 and the lateral cortex10. CCI provides an easy and accurate method of investigating the effects and potential treatments for TBIs.
In addition to the CCI model, the fluid percussion and weight drop models are commonly used to produce TBIs. However, these models present limitations, including less control over injury parameters, producing histopathalogical changes not seen in human TBIs, and greater incidence of accidental death in mice3,5,10. The blast wave model is also used to produce TBIs. Although the blast wave model does not reproduce the histopathalogical changes seen following a mechanical impact, this model does accurately produce TBIs experienced particularly by military personnel11. The controlled cortical impact model is easy to control due to the precise control over deformation parameters such as time, velocity, and depth of impact5. Such accuracy makes replicating nearly identical injuries across an entire group of animals more feasible. Most importantly, CCI reproduces TBIs with features seen in human TBIs12. However, there is no single animal model that is entirely successful in reproducing the complete spectrum of pathological changes observed after TBI. Further research is necessary to fully reveal the acute and chronic changes that occur after TBI.
Two types of injuries occur following a TBI: primary and secondary injuries. The primary injury occurs at the moment of impact and is not sensitive to therapeutic treatments; however, the secondary injuries that persist after the initial injury are subject to treatments13. The controlled cortical impact model produces the primary injury, thus allowing researchers to investigate the effects of TBI and potential therapeutic treatments for the potentially long-lasting effects of secondary injuries. Areas of potential research using the CCI model include neuronal death, cerebral edema, neurogenesis, vascular effects, histopathalogical changes, and memory deficits and more3,13-16.

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controlled cortical impact model for traumatic brain injury

Every year over a million Americans suffer a traumatic brain injury (TBI). Combined with the incidence of TBIs worldwide, the physical, emotional, social, and economical effects are staggering. Therefore, further research into the effects of TBI and effective treatments is necessary. The controlled cortical impact (CCI) model induces traumatic brain injuries ranging from mild to severe. This method uses a rigid impactor to deliver mechanical energy to an intact dura exposed following a craniectomy. Impact is made under precise parameters at a set velocity to achieve a pre-determined deformation depth. Although other TBI models, such as weight drop and fluid percussion, exist, CCI is more accurate, easier to control, and most importantly, produces traumatic brain injuries similar to those seen in humans. However, no TBI model is currently able to reproduce pathological changes identical to those seen in human patients. The CCI model allows investigation into the short-term and long-term effects of TBI, such as neuronal death, memory deficits, and cerebral edema, as well as potential therapeutic treatments for TBI.

The controlled cortical impact model produces TBIs ranging in severity from mild to severe. Post-impact the amount of cranial swelling, bleeding, and cranial distortion at the impact site will reveal the injury severity resulting from the speed and deformation depth parameters. Mild TBIs result in cranial swelling at the impact site and slight bleeding due to the limited dura breach. A moderate TBI exhibits cranial swelling and increased bleeding due to dura breach upon impaction (Figure 1). The differen...

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Controlled Cortical Impact Model for Traumatic Brain Injury

Traumatic brain injuries (TBIs) remain a serious health problem. Using the controlled cortical impact surgery model, research on the effects of TBI and possible treatment methods may be performed.

Every year over a million Americans suffer a traumatic brain injury (TBI).  Combined with the incidence of TBIs worldwide, the physical, emotional, ...

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28.4K vues.  Indiana University School of Medicine. Traumatic brain injuries (TBIs) remain a serious health problem. Using the controlled cortical impact surgery model, research on the effects of TBI and possible treatment methods may be performed.

Vidéo: Controlled Cortical Impact Model for Traumatic Brain Injury

Pressure Controlled Ventilation to Induce Acute Lung Injury in Mice

Murine models are extensively used to investigate acute injuries of different organs systems (1-34). Acute lung injury (ALI), which occurs with prolonged mechanical ventilation, contributes to morbidity and mortality of critical illness, and studies on novel genetic or pharmacological targets are areas of intense investigation (1-3, 5, 8, 26, 30, 33-36). ALI is defined by the acute onset of the disease, which leads to non-cardiac pulmonary edema and subsequent impairment of pulmonary gas exchange (36). We have developed a murine model of ALI by using a pressure-controlled ventilation to induce ventilator-induced lung injury (2). For this purpose, C57BL/6 mice are anesthetized and a tracheotomy is performed followed by induction of ALI via mechanical ventilation. Mice are ventilated in a pressure-controlled setting with an inspiratory peak pressure of 45 mbar over 1 - 3 hours. As outcome parameters, pulmonary edema (wet-to-dry ratio), bronchoalveolar fluid albumin content, bronchoalveolar fluid and pulmonary tissue myeloperoxidase content and pulmonary gas exchange are assessed (2). Using this technique we could show that it sufficiently induces acute lung inflammation and can distinguish between different treatment groups or genotypes (1-3, 5). Therefore this technique may be helpful for researchers who pursue molecular mechanisms involved in ALI using a genetic approach in mice with gene-targeted deletion.

A murine model for ventilator induced lung injury is an important tool to study an acute lung injury in vivo. Here, we report an easy applicable in situ model for acute lung injury using high-pressure mechanical ventilation to induce acute failure of the lung.

Murine models are extensively used to investigate acute injuries of different organs systems (1-34). Acute lung injury (ALI), which occurs with prolonged ...

Intraspinal Cell Transplantation for Targeting Cervical Ventral Horn in Amyotrophic Lateral Sclerosis and Traumatic Spinal Cord Injury

Respiratory compromise due to phrenic motor neuron loss is a debilitating consequence of a large proportion of human traumatic spinal cord injury (SCI) cases 1 and is the ultimate cause of death in patients with the motor neuron disorder, amyotrophic laterals sclerosis (ALS) 2.
ALS is a devastating neurological disorder that is characterized by relatively rapid degeneration of upper and lower motor neurons. Patients ultimately succumb to the disease on average 2-5 years following diagnosis because of respiratory paralysis due to loss of phrenic motor neuron innnervation of the diaphragm 3. The vast majority of cases are sporadic, while 10% are of the familial form. Approximately twenty percent of familial cases are linked to various point mutations in the Cu/Zn superoxide dismutase 1 (SOD1) gene on chromosome 21 4. Transgenic mice 4,5 and rats 6 carrying mutant human SOD1 genes (G93A, G37R, G86R, G85R) have been generated, and, despite the existence of other animal models of motor neuron loss, are currently the most highly used models of the disease.
Spinal cord injury (SCI) is a heterogeneous set of conditions resulting from physical trauma to the spinal cord, with functional outcome varying according to the type, location and severity of the injury 7. Nevertheless, approximately half of human SCI cases affect cervical regions, resulting in debilitating respiratory dysfunction due to phrenic motor neuron loss and injury to descending bulbospinal respiratory axons 1. A number of animal models of SCI have been developed, with the most commonly used and clinically-relevant being the contusion 8.
Transplantation of various classes of neural precursor cells (NPCs) is a promising therapeutic strategy for treatment of traumatic CNS injuries and neurodegeneration, including ALS and SCI, because of the ability to replace lost or dysfunctional CNS cell types, provide neuroprotection, and deliver gene factors of interest 9.
Animal models of both ALS and SCI can model many clinically-relevant aspects of these diseases, including phrenic motor neuron loss and consequent respiratory compromise 10,11. In order to evaluate the efficacy of NPC-based strategies on respiratory function in these animal models of ALS and SCI, cellular interventions must be specifically directed to regions containing therapeutically relevant targets such as phrenic motor neurons. We provide a detailed protocol for multi-segmental, intraspinal transplantation of NPCs into the cervical spinal cord ventral gray matter of neurodegenerative models such as SOD1G93A mice and rats, as well as spinal cord injured rats and mice 11.

Neural precursor transplantation is a promising strategy for protecting and/or replacing lost/dysfunctional cervical phrenic motor neurons in spinal cord injury (SCI) and the motor neuron disorder, amyotrophic laterals sclerosis (ALS). We provide a protocol for cell delivery to cervical spinal cord ventral horn in rodent models of ALS and SCI.

Respiratory compromise due to phrenic motor neuron loss is a debilitating consequence of a large proportion of human traumatic spinal cord injury (SCI) ...

Controlled Cervical Laceration Injury in Mice

Use of genetically modified mice enhances our understanding of molecular mechanisms underlying several neurological disorders such as a spinal cord injury (SCI). Freehand manual control used to produce a laceration model of SCI creates inconsistent injuries often associated with a crush or contusion component and, therefore, a novel technique was developed. Our model of cervical laceration SCI has resolved inherent difficulties with the freehand method by incorporating 1) cervical vertebral stabilization by vertebral facet fixation, 2) enhanced spinal cord exposure, and 3) creation of a reproducible laceration of the spinal cord using an oscillating blade with an accuracy of &plusmn;0.01 mm in depth without associated contusion. Compared to the standard methods of creating a SCI laceration such as freehand use of a scalpel or scissors, our method has produced a consistent lesion. This method is useful for studies on axonal regeneration of corticospinal, rubrospinal, and dorsal ascending tracts.

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 &plusmn;0.01 mm.

Use of genetically modified mice enhances our  understanding of molecular mechanisms underlying several neurological disorders  such as a spinal cord ...

Stretch in Brain Microvascular Endothelial Cells (cEND) as an In Vitro Traumatic Brain Injury Model of the Blood Brain Barrier

Due to the high mortality incident brought about by traumatic brain injury (TBI), methods that would enable one to better understand the underlying mechanisms involved in it are useful for treatment. There are both in vivo and in vitro methods available for this purpose. In vivo models can mimic actual head injury as it occurs during TBI. However, in vivo techniques may not be exploited for studies at the cell physiology level. Hence, in vitro methods are more advantageous for this purpose since they provide easier access to the cells and the extracellular environment for manipulation.
Our protocol presents an in vitro model of TBI using stretch injury in brain microvascular endothelial cells. It utilizes pressure applied to the cells cultured in flexible-bottomed wells. The pressure applied may easily be controlled and can produce injury that ranges from low to severe. The murine brain microvascular endothelial cells (cEND) generated in our laboratory is a well-suited model for the blood brain barrier (BBB) thus providing an advantage to other systems that employ a similar technique. In addition, due to the simplicity of the method, experimental set-ups are easily duplicated. Thus, this model can be used in studying the cellular and molecular mechanisms involved in TBI at the BBB.

Stretch in Brain Microvascular Endothelial Cells cEND as an In Vitro Traumatic Brain Injury Model of the Blood Brain Barrier

In vitro traumatic brain injury models are being developed to reproduce in vivo brain deformation. Stretch-induced injury has been employed for astrocytes, neurons, glial cells, aortic, and brain endothelial cells. However, our system uses a blood brain barrier (BBB) model that possesses properties constituting a legitimate model of the BBB to establish an in vitro&#160;TBI model.

Due to the high mortality incident brought about by traumatic brain injury (TBI), methods that would enable one to better understand the underlying ...

Renal Ischaemia Reperfusion Injury: A Mouse Model of Injury and Regeneration

Renal ischaemia reperfusion injury (IRI) is a common cause of acute kidney injury (AKI) in patients and occlusion of renal blood flow is unavoidable during renal transplantation. Experimental models that accurately and reproducibly recapitulate renal IRI are crucial in dissecting the pathophysiology of AKI and the development of novel therapeutic agents. Presented here is a mouse model of renal IRI that results in reproducible AKI. This is achieved by a midline laparotomy approach for the surgery with one incision allowing both a right nephrectomy that provides control tissue and clamping of the left renal pedicle to induce ischaemia of the left kidney. By careful monitoring of the clamp position and body temperature during the period of ischaemia this model achieves reproducible functional and structural injury. Mice sacrificed 24 hr&#160;following surgery demonstrate loss of renal function with elevation of the serum or plasma creatinine level as well as structural kidney damage with acute tubular necrosis evident. Renal function improves and the acute tissue injury resolves during the course of 7 days following renal IRI such that this model may be used to study renal regeneration. This model of renal IRI has been utilized to study the molecular and cellular pathophysiology of AKI as well as analysis of the subsequent renal regeneration.

The mouse model of renal ischaemia reperfusion injury described here comprises of a right nephrectomy that provides control tissue and clamping of the left renal pedicle to induce ischaemia that results in acute kidney injury. This model uses a midline laparotomy approach with all steps performed via one incision.

Renal ischaemia reperfusion injury (IRI) is a common cause of acute kidney injury (AKI) in patients and occlusion of renal blood flow is unavoidable ...

A Novel Model of Mild Traumatic Brain Injury for Juvenile Rats

Despite growing evidence that childhood represents a major risk period for mild traumatic brain injury (mTBI) from sports-related concussions, motor vehicle accidents, and falls, a reliable animal model of mTBI had previously not been developed for this important aspect of development. The modified weight-drop technique employs a glancing impact to the head of a freely moving rodent transmitting acceleration, deceleration, and rotational forces upon the brain. When applied to juvenile rats, this modified weight-drop technique induced clinically relevant behavioural outcomes that were representative of post-concussion symptomology. The technique is a rapidly applied procedure with an extremely low mortality rate, rendering it ideal for high-throughput studies of therapeutics. In addition, because the procedure involves a mild injury to a closed head, it can easily be used for studies of repetitive brain injury. Owing to the simplistic nature of this technique, and the clinically relevant biomechanics of the injury pathophysiology, the modified weight-drop technique provides researchers with a reliable model of mTBI that can be used in a wide variety of behavioural, molecular, and genetic studies.

The modified weight-drop technique is an easy, cost-effective procedure used for the induction of mild traumatic brain injury in juvenile rats. This novel technique produces clinically relevant symptomology that will advance the study of mild traumatic brain injury (mTBI) and concussion.

Despite growing evidence that childhood represents a major risk period for mild traumatic brain injury (mTBI) from sports-related concussions, motor ...

Calibrated Forceps Model of Spinal Cord Compression Injury

Compression injuries of the murine spinal cord are valuable animal models for the study of spinal cord injury (SCI) and spinal regenerative therapy. The calibrated forceps model of compression injury is a convenient, low cost, and very reproducible animal model for SCI. We used a pair of modified forceps in accordance with the method published by Plemel et al. (2008) to laterally compress the spinal cord to a distance of 0.35 mm. In this video, we will demonstrate a dorsal laminectomy to expose the spinal cord, followed by compression of the spinal cord with the modified forceps. In the video, we will also address issues related to the care of paraplegic laboratory animals. This injury model produces mice that exhibit impairment in sensation, as well as impaired hindlimb locomotor function. Furthermore, this method of injury produces consistent aberrations in the pathology of the SCI, as determined by immunohistochemical methods. After watching this video, viewers should be able to determine the necessary supplies and methods for producing SCI of various severities in the mouse for studies on SCI and/or treatments designed to mitigate impairment after injury.

Spinal cord injury models should be highly reproducible. We demonstrate that the calibrated forceps compression model of spinal cord injury is an easy to use surgical method for generating reproducible injuries to the murine spinal cord.

Compression injuries of the murine spinal cord are valuable animal models for the study of spinal cord injury (SCI) and spinal regenerative therapy. The ...

A Tissue Displacement-based Contusive Spinal Cord Injury Model in Mice

Producing a consistent and reproducible contusive spinal cord injury (SCI) is critical to minimizing behavioral and histological variabilities between experimental animals. Several contusive SCI models have been developed to produce injuries using different mechanisms. The severity of the SCI is based on the height that a given weight is dropped, the injury force, or the spinal cord displacement. In the current study, we introduce a novel mouse contusive SCI device, the Louisville Injury System Apparatus (LISA) impactor, which can create a displacement-based SCI with high injury velocity and accuracy. This system utilizes laser distance sensors combined with advanced software to produce graded and highly-reproducible injuries. We performed a contusive SCI at the 10th thoracic vertebral (T10) level in mice to demonstrate the step-by-step procedure. The model can also be applied to the cervical and lumbar spinal levels.

We introduce a tissue displacement-based contusive spinal cord injury model that can produce a consistent contusive spinal cord injury in adult mice.

Producing a consistent and reproducible contusive spinal cord injury (SCI) is critical to minimizing behavioral and histological variabilities between ...

A Mouse Model of Single and Repetitive Mild Traumatic Brain Injury

Mild Traumatic Brain Injury (mTBI) can result in the acute loss of brain function, including a period of confusion, a loss of consciousness (LOC), focal neurological deficits and even amnesia. Athletes participating in contact sports are at high risk of exposure to large number of mTBIs. In terms of the level of injury in a sporting athlete, a mTBI is defined as a mild injury that does not cause gross pathological changes, but does cause short-term neurological deficits that are spontaneously resolved. Despite previous attempts to model mTBI in mice and rats, many have reported gross adverse effects including skull fractures, intracerebral bleeding, axonal injury and neuronal cell death. Herein, we describe our highly reproducible animal model of mTBI that reproduces clinically relevant symptoms. This model uses a custom made pneumatic impactor device to deliver a closed-head trauma. This impact is made under precise velocity and deformation parameters, creating a reliable and reproducible model to examine the mechanisms that contribute to effects of single or repetitive concussive mTBI.

Athletes absorb several hundred mild traumatic brain injuries (mTBI)/concussions every year; however, the consequence of these on the brain is poorly understood. Therefore, an animal model of single and repetitive mTBI that consistently replicates clinically relevant symptoms provides the means to advance the study of mTBI and concussion.

Mild Traumatic Brain Injury (mTBI) can result in the acute loss of brain function, including a period of confusion, a loss of consciousness (LOC), focal ...

Semi-quantitative Assessment Using [18F]FDG Tracer in Patients with Severe Brain Injury

Patients with severe traumatic brain injury (sTBI) have difficulty knowing whether they are accurately expressing their thoughts and emotions because of disorders of consciousness, disrupted higher brain function, and verbal disturbances. As a consequence of an insufficient ability to communicate, objective evaluations are needed from family members, medical staff, and caregivers. One such evaluation is the assessment of functioning brain areas. Recently, multimodal brain imaging has been used to explore the function of damaged brain areas. [18F]-fluorodeoxyglucose positron emission tomography-computed tomography ([18F]FDG-PET/CT) is a successful tool for examining brain function. However, the assessment of brain glucose metabolism based on [18F]FDG-PET/CT is not standardized and depends on several varying parameters, as well as the patient&#39;s condition. Here, we describe a series of semiquantitative assessment protocols for a region-of-interest (ROI) image analysis using self-produced [18F]FDG tracers in patients with sTBI. The protocol focuses on screening the participants, preparing the [18F]FDG tracer in the hot lab, scheduling the acquisition of [18F]FDG-PET/CT brain images, and measuring glucose metabolism using the ROI analysis from a targeted brain area.

Semi-quantitative Assessment Using [18F]FDG Tracer in Patients with Severe Brain Injury

[18F]-fluorodeoxyglucose (FDG) positron emission tomography-computed tomography is useful for studying glucose metabolism related to brain function. Here, we present a protocol for an [18F]FDG tracer set-up and semiquantitative assessment of the region-of-interest analysis for targeted brain areas associated with clinical manifestations in patients with severe traumatic brain injury.

Patients with severe traumatic brain injury (sTBI) have difficulty knowing whether they are accurately expressing their thoughts and emotions because of ...