The authors would like to thank Irene Ma, Rose Tobais, and Jong Rho for their technical assistance. Funding was provided to MJE by the Department of Pediatrics at the University of Calgary, the Alberta Children&#8217;s Hospital Foundation (ACHF) and the Alberta Children&#8217;s Hospital Research Institute (ACHRI). The Postdoctoral fellowship for RM was provided by ACHF.

注：全ての実験は、動物管理のカナダ人評議会に合わせて実施し、カルガリー大学、動物ケア倫理委員会によって承認された。 1.繁殖と動物の準備<ol><li>標準繁殖プロトコルに従って、社内標準の実験動物のサプライヤーや品種の仔から妊娠ラットを注文。 </li><li>暗サイクル：食物および水を自由摂取アクセスハウスのすべての動物を、温度制御されたラット収容室（21℃）で、そのは、12：12時間の明に維持されている。 </li><li>子犬は生後21日目（P21）に到達すると、3または4の同性グループで母親と家から子犬を離乳させる。 </li></ol>軽度外傷性脳損傷（MTBI）装置の2.セットアップ<ol><li>所望の質量（ 例えば、150グラム）の手順、ミル重みの開始前。安全に釣り糸が第ことを可能にする重量の上端に金属ループを取り付ける重みにXED。 </li><li>鋭利なカミソリの刃でスズ箔のスコア。得点スズ箔は、ラットの体重をサポートしていますが、重量が頭部衝撃後のラットの加速に干渉しないことを確認してください。 </li><li>それはピンと張っているように、コレクションのスポンジ（38×25×15 cm 3）で（ 図1）を含むテープ透明なプラスチック（38のx 27 xは27センチメートル3）からなるU字形の段階にスコア化スズ箔。 </li><li>透明なプラスチック製のガイドチューブの下の正しい位置にU字型のプラスチック製のステージを置く。 </li><li>クランプスタンド付きの場所にプラスチック製のガイドチューブ（X 1.5メートル2.2センチメートル径）を持ち、それが3.5センチメートル得点スズ箔の上になるようにガイドチューブを配置する。 </li><li>体重の底が自由に2.5センチメートル得点スズ箔の上にハングアップすることを確実に重量に金属ループを通して釣り糸を取り付けます。 </li><li>確実にクランプスタンドに釣り糸を添付。 注：ハマグリに重みをテザリングラットは、コレクションスポンジへの影響）から落下している間スズ箔上2.5センチメートルの高さでのpスタンドは再ヒットを防ぎます。 </li><li>釣り糸でプラスチック製のガイドチューブを通して体重を引き上げ、1.0メートルで、六角レンチピンで所定の位置にそれを保持する。 </li></ol> MTBIの3誘導<ol><li>ラットは、手続きの部屋にP30の移動ケージに達すると。 </li><li>イソフルランチャンバー内にラットを置き、足や尾ピンチに非応答になるまで軽くラットを麻酔。 </li><li>すばやく落錘のパスで直接その頭を放ちスズ箔上のラットの胸ダウンを置く。 図2を参照してください。ラットが移動したり、ウェイクアップ、それが得点スズ箔上に配置することができる前に、足や尾ピンチに非応答するまで、イソフルラン室に戻り、再び開始するために開始されます。 </li><li>重量はプラスチック製のガイドチューブを垂直に落下し、頭の上にラットを打つできるように、アレンキーピンを引き。目Eラットは急速に仰臥位で180°回転し、土地を受けることになる。 </li><li>すぐに収集スポンジからラットを削除し、綿先端アプリケーターでラットの頭部への局所リドカインを適用します。 </li><li>市販の加熱パッド上にそれを設定することによって加熱されるクリーンケージ内の仰臥位でラットを置きます。 </li><li>ストップウォッチを使用して、またはデジタルタイマーは、「時間から右へ」を取得する。タイム·トゥ·右は、麻酔から覚ますと発生しやすい位置に仰臥位から​​フリップやウォーキングを開始するために、ラットに要する時間である。 </li><li>それは通常の動作（グルーミング、ウォーキング、探検など ） を回復した後にそのホームケージにラットを返す。 </li><li>繰り返しますMTBIを必要とする追加の各ラットについて3.2から3.8を繰り返します。 </li><li>繰り返しのMTBI実験のために複数の時点で同じラットに手順を繰り返します。 </li></ol>シャム傷害の4誘導<ol><li>軽くアネスト岩田それは足や尾のピンチに非応答になるまで、イソフルランでラットをhetize。 </li><li>すばやく落錘のパスで直接その頭を放ちスズ箔上のラットの胸ダウンを置く。 </li><li>プラスチック製のガイドチューブからアレンキーピンを引いたことなく、スズ箔からラットを取り出し、綿先端アプリケーターでラットの頭部への局所リドカインを適用します。 </li><li>市販の加熱パッド上にそれを設定することによって加熱されるクリーンケージ内の仰臥位でラットを置きます。 </li><li> 「時間から右へ」を取得するためにストップウォッチやデジタルタイマーを使用してください。 </li><li>それは通常の動作（グルーミング、ウォーキング、探検など ） を回復した後にそのホームケージにラットを返す。 </li></ol>ビームによるMTBI 5.実証試験8ウォーキング <ol><li>手続き部屋にMTBIまたは偽傷害の戻り動物の誘導後24時間。 </li><li>クリーン保持ケージにラットを転送と家庭ケージのオープンエンド部分はビームの狭い側を向くように165センチメートルテーパービームの狭い最後にラットのホームケージを置く。 注：テーパービーム165センチです。ビームの中心プラットフォームは、ワイド端で6センチ狭い端1.75センチ幅を有する。中心ビームが時ラットの足スリップ安全性を提供する棚部（幅2cmとセンタービーム2以下cm）を有している。テスト中にビームから落ちる可能性ラットへの傷害の危険を減らすために、ビーム下のフォームパッドを配置します。 </li><li>テーパー梁のワイド端でビデオカメラを置き、位置/ビデオを見て研究者が明らかにテーパービームの全長のためにラットの動きを見ることができることを保証するためにビデオカメラをズーム。 </li><li>テーパー梁のワイド端にラットを置き、そのホームケージにビームを歩いて渡ることをお勧めします。ラットがテーパー状ビームを横切ると、レイに少なくとも60秒間そのホームケージにラットを残すターゲットの場所をのnForce。これは試験＃1であり、分析には含まれていません。 </li><li>上のビデオカメラの電源を入れ、ラットは、ビーム歩行タスクを4回追加（ホームケージで60秒の強化期間を維持する）を完了することができます。ラットはすべての試験を完了すると、そのホームケージにラットを返す。 </li><li>スコアに、発生し、時間/期間は、個々の試験のために、ビームを横断する後肢の足-スリップの数を記録。各ラットについて、ビームを横切るように後肢足グラスと時間の平均数を計算するためにこのデータを使用する。 </li></ol>

<ol>
	<li>DeWitt, D., Perez-Polo, R., Hulsebosch, C., Dash, P., Robertson, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Challenges+in+the+development+of+rodent+models+of+mild+traumatic+brain+injury.">Challenges in the development of rodent models of mild traumatic brain injury.</a> Journal of Neurotrauma. 30, 688-701 (2013).</li><li>Xiong, Y., Mahmood, A., Chopp, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Animal+models+of+traumatic+brain+injury.">Animal models of traumatic brain injury.</a> Nature Reviews Neuroscience. 14, 128-142 (2013).</li><li>Zhang, Z., Lerner, S., Kobiessy, F., Hayes, R., Wang, K., Yan, Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Systems+biology+and+the+anostic+approach+to+drug+discovery+and+development+to+treat+traumatic+brain+injury.">Systems biology and the anostic approach to drug discovery and development to treat traumatic brain injury.</a> Systems Biology in Drug Discovery and Development: Methods and Protocols, Methods in Molecular Biology. , .</li><li>Viano, D., Casson, I., Pellmen, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Concussion+in+profession+football:+Biomechanics+of+the+struck+player+-+Part+14.">Concussion in profession football: Biomechanics of the struck player - Part 14.</a> Neurosurgery. 61, 313-327 (2007).</li><li>Marmarou, 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=A+new+model+of+diffuse+brain+injury+in+rats:+Part+1+-+Pathophysiology+and+biomechanics.">A new model of diffuse brain injury in rats: Part 1 - Pathophysiology and biomechanics.</a> Journal of Neurosurgery. 80, 291-300 (1994).</li><li>Mychasiuk, R., Farran, A., Esser, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assessment+of+an+experimental+rodent+model+of+pediatric+mild+traumatic+brain+injury.">Assessment of an experimental rodent model of pediatric mild traumatic brain injury.</a> Journal of Neurotrauma. 31 (8), (2014).</li><li>Kane, M., 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+mouse+model+of+human+repetitive+mild+traumatic+brain+injury.">A mouse model of human repetitive mild traumatic brain injury.</a> Journal of Neuroscience Methods. 203, 41-49 (2012).</li><li>Schallert, T., Woodlee, M., Fleming, S., Krieglstein, J., Klumpp, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Disentangling+multiple+types+of+recovery+from+brain+injury.">Disentangling multiple types of recovery from brain injury.</a> Pharmacology of Cerebral Ischemia. , (2002).</li><li>Mychasiuk, R., Hehar, H., Farran, A., Esser, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mean+Girls:+Sex+differences+in+the+effects+of+mild+traumatic+brain+injury+on+the+social+dynamics+of+juvenile+rat+play+behaviour.">Mean Girls: Sex differences in the effects of mild traumatic brain injury on the social dynamics of juvenile rat play behaviour.</a> Behavioural Brain Research. 259, (2014).</li><li>Centers for Disease Control and Prevention. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Report to congress on mild traumatic brain injury in the United States: Steps to prevent a serious public health problem. , 1-47 (2003).</li></ol>

No competing financial interests exist.

Reliable modelling systems are needed to effectively cultivate basic science research that has significant translational validity. In response to rising occurrences and popular media, the investigation of mTBI and concussion has become a priority in many disciplines. However, despite increased research, there have been only incremental improvements in therapeutic strategies and treatment options 3. This lack of progress may be partially due to a discrepancy between the modeling systems employed and actual injury etiology. The majority of studies utilized rodent models that failed to reproduce the important biomechanical forces and appropriate post-injury symptomology. The current human definition of mTBI specifies that the injury results from acceleration and deceleration forces associated with a blunt trauma 10. The modified weight drop technique described here is therefore an ideal model for the study of mTBI and concussion because it uses a glancing impact to cause rapid rotational acceleration and deceleration to the head of an unrestrained animal, mimicking the biomechanical forces identified in sports-related injuries and automobile accidents. In addition, this model is easily adapted to examine repetitive mTBI, a phenomena that is emerging as a serious medical and socioeconomic issue. Studies indicate that rodents may be exposed to a series of 10 distinct mTBIs with minimal mortality 7. Finally, the method is inexpensive and can be carried out rapidly, allowing for high-throughput examination of a many therapeutic compounds and treatment regiments. 
Just as with any procedural technique, certain aspects of the protocol are particularly important to the generation of reliable results. First, the tin foil needs to be scored effectively. If the tin foil is not properly scored, the force imparted by the weight during the glancing impact will not be enough to propel the juvenile rat through the tin foil onto the collection sponge. In these situations, the rat will remain in the starting position (chest down on the tin foil) and the mTBI will result from the blunt trauma from the weight impacting the stationary head, not the rotational acceleration and deceleration desired. Second, during the induction of the mTBI and the sham injury, the level of anesthetic applied to each rat should be consistent. Owing to the fact that time-to-right is used as marker of mTBI, the researcher should try to ensure that animals receiving a mTBI and animals receiving a sham injury are exposed to similar levels of anesthetic. A major advantage to this technique over many other TBI procedures is the low level and duration of anesthesiology. However, the juvenile rat needs to be non-responsive to a toe or tail pinch to ensure they do not wake-up on the stage before the injury is induced. Finally, in order to maintain a consistent injury etiology, the positioning of the rat&#8217;s head is particularly important. Ideally the weight should impact the center of the dorsal surface of the head. Caution should be taken to avoid positioning the path of the weight too near the caudal/posterior portion of the head, as impacting the brainstem and cerebellum is associated with increased mortality and seizure activity. 
Based upon the biomechanical pathophysiology of injury induction and the behavioural outcomes examined, the modified weight-drop technique appears to be a reliable model for the investigation of paediatric mTBI and concussion. Although preliminary studies of this novel model have assessed some basic molecular and structural changes 7 future studies will be needed to ascertain how the brain responds to a mTBI with this injury etiology. An in-depth analysis of the neuroanatomical and biological changes that occur at the cellular and epigenetic level would increase model validity and translational applicability. In addition to stimulating the generation of targeted pharmacological therapies, understanding the pathophysiological changes that occur in the brain in response to mTBI and concussion would also direct the research related to clinical biomarkers that have the ability to predict outcomes following injury.

中等度から重度の外傷性脳損傷（TBI）の生成のための多くの広く使用されている方法があるが、非常に少数の技術は穏やかな誘導するために開発されており、げっ歯類における頭部外傷を閉じた。軽度の外傷性脳損傷（MTBI）は1を組み合わせた中等度および重度の脳損傷の3倍一般的であるという事実のために、MTBIの信頼性モデルは、病態生理、神経生物学および行動の結果、および治療 ​​戦略に関する研究を促進するために必要とされる。たとえば、200の上にありました、過去10年間で、現在の動物モデル2の制限などの理由では、TBI 3の治療のための臨床薬物試験を失敗した。モデリングシステムはトランスレーショナルリサーチ研究のために生成される場合、調査結果の適用が実装モデルの妥当性に依存している。 MTBI /脳震盪の研究のために、信頼性の高い動物モデルは、生体力学的な力のresponを模倣していないだろう傷害の病因のためsibleするだけでなく、臨床的に関連する人口によって報告されたものと一致する症状を誘発するだろう。子供はMTBI特に高い危険にさらされているので、また、最適なモデリングシステムは、成人同等に加えて、若い少年げっ歯類に適用可能である。 選手がmTBIsまたは震とう脳損傷を負っているような状況の生体力学的分析は怪我のために最も重要な予測因子は、急速なヘッド加速と高速の影響4であることを示している。現在TBIの誘導のために用いられるげっ歯類モデルの大部分は、ヘッド5（総説については2を参照）のほとんど又は全く動きを可能にする。ここで概説モデルは、被験者の頭と体に加速/減速力を加える180°回転し、自由落下を伴う物理的に拘束されていない幼若ラットの頭部に高速のインパクトを実現します。 Tここでは、MTBIの誘導のため、この修正された重量損失の技術に関連する2つの主要な利点である。まず、モデルは（6を参照の行動の結果の完全な説明のために）は、脳への明白な損傷を与えることなく、症状のような震とう臨床的に関連を生成します。また、この修正された重量ドロップ技術が異質な成果をポスト震とう症候群の臨床報告と一致して生成します。 MTBIの影響が有意であるが、複数のアウトカム指標に検討したときにMTBIを経験したげっ歯類の間に実質的な変動がある。第二に、この方法は、反復MTBI 7の研究を可能にします。既存のTBIモデルの大部分は重篤な傷害を負わせるように、全体の皮質への広範​​な損傷を与えることなく、反復的なTBIを研究するために第二の損傷、およびほぼ不可能を誘導することがしばしば困難である。 したがって、寄り付きために改変重量ドロップ技術を使用する主な根拠MTBIのctionはより密接に脳震盪と少年集団における反復的なTBIの病態生理と症状を表してけがを生成することである。スポーツに関連するMTBIの発生率の増加により、落下し、自動車事故、特に小児期に、MTBIのこのユニークなげっ歯類モデルが簡単に複数のヒットに適用することができ震とうのような脳損傷の研究のための貴重なツールと研究者を提供していますパラダイム。

<table border="0" cellpadding="0" cellspacing="0" width="824">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:264px;">Brass Weights</td>
			<td style="width:155px;">Ginsberg Scientific</td>
			<td style="width:187px;">7-2500-2</td>
			<td style="width:219px;">Need to have metal loop attached to base</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:264px;">Alluminum Foil</td>
			<td style="width:155px;">Alcan</td>
			<td style="width:187px;"></td>
			<td>Available at most grocery stores</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:264px;">Masking Tape</td>
			<td style="width:155px;"></td>
			<td style="width:187px;"></td>
			<td>Commercially available&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:264px;">U-Shaped Plastic Stand</td>
			<td style="width:155px;"></td>
			<td style="width:187px;"></td>
			<td>Constructed by Laboratory</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:264px;">Clamp Stand</td>
			<td style="width:155px;">Sigma-Aldrich</td>
			<td style="width:187px;">Z190357</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:264px;">Plastic Guide Tube</td>
			<td style="width:155px;"></td>
			<td style="width:187px;"></td>
			<td>Could be constructed or purchased at a hardware store</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:264px;">Fishing Line</td>
			<td style="width:155px;">Angler 10lb&#160;</td>
			<td style="width:187px;"></td>
			<td>Purchased from a sporting goods retailer&#160;</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:264px;">Isoflurane</td>
			<td style="width:155px;">Pharmaceutical Partners of Canada</td>
			<td style="width:187px;">DIN 02237518</td>
			<td>Inhalation Anesthetic</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:264px;">Topical Lidocaine (30ml)</td>
			<td style="width:155px;">Astra Zeneca</td>
			<td style="width:187px;">DIN 0001694</td>
			<td>Xylocaine Jelly 2%&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:264px;">Cotton Swabs</td>
			<td style="width:155px;"></td>
			<td style="width:187px;"></td>
			<td>Commercially available&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:264px;">Heating Pad - 3 heat setting</td>
			<td style="width:155px;"></td>
			<td style="width:187px;"></td>
			<td>Commercially available&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:264px;">Stop Watch</td>
			<td style="width:155px;">Sportline</td>
			<td style="width:187px;">L303</td>
			<td>Purchased from a sporting goods retailer&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:264px;">Video Camera</td>
			<td style="width:155px;">Sony</td>
			<td style="width:187px;">HDR-CX260V</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:264px;">Sprague Dawley Rats</td>
			<td style="width:155px;">Charles River Laboratories</td>
			<td style="width:187px;">SAS SD 40</td>
			<td>Male and females ordered from Charles River Laboratories and pups bred in-house</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:264px;">Balance Beam</td>
			<td></td>
			<td></td>
			<td>Constructed by Laboratory</td>
		</tr>
	</tbody>
</table>

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.

上述の修正された重量ドロップ手法は幼若ラットにおける軽度の外傷性脳損傷（MTBI）の誘導のために信頼できる方法である。 150グラムの影響の重みを利用して、この技術は、成功して50〜120グラムの範囲幼若ラットに適用されている。また、手順が簡単に反復MTBIの研究のために同じ動物で繰り返すことができる。 （ 図3）シングルMTBIの展示の時間から右への増加を経験すると思われる動物は起床時に唖然とするが、それらは急速に正常な活動を再開し、シャム損傷動物からの視覚的に区別できない。傷害がかすめる影響に関連するすべての痛みがなくなり、穏やかな、局所リドカインであることを考えると、必要な唯一の鎮痛薬である。鎮痛剤は、一般的な炎症性および回復プロセスを妨害することが知られているように、この研究のために重要である。明白な症状がないため、ビーム歩行タスクがに信頼性があるMTBIの誘導を検証するために使用することができるオール。それは、MTBIを経験していないすべての動物は、ビーム歩行タスク上の欠損を示すことが、注意することが重要であるが、偽の負傷と少年ラットと比較した場合、グループとして、MTBIを持つ少年ラットは、かなり多くの後肢の足-スリップを実証する（ 図4）。 この修​​正された重量ドロップ技術のもう一つの重要な特徴は、傷害の誘導中幼若ラットに適用される拘束の欠如である。急速な回転加速と減速が続くヘッドにかすめる打撃を提供することにより、このモデルは、より密接にMTBIと脳震盪に起因する生体力学的な力を表している。この手順は、若年ラットまたは成体マウスに適用した場合、死亡率は極めて低い（202分の7幼若動物〜3.4％の死亡率）、及び頭蓋骨骨折および頭蓋内の出血は6,7非常に稀である。さらに、このモデルは、臨床的に関連SYを生成mptomology。シングルMTBIを経験した少年げっ歯類は、抑う ​​つ様行動の増加実行機能の欠損、および変更された社会的相互作用6,9と一緒に、バランスとモーター行動の赤字を示した。同様に、成体マウスは、時間7で回復する軽度のバランスと協調赤字を表示します。最後に、このモデルを用いてMTBIの誘導が最小限の麻酔薬を必要とする外科的調製を含むか、頭蓋骨に穴を掘るしない。結果は、したがって、手術や麻酔薬によってトリガ交絡炎症や免疫学的効果によってバイアスされていません。さらに、急速な回復時間と開放創の欠如は、げっ歯類がMTBIを体験した直後に発生する追加試験パラダイムの開始を可能にします。 <img alt="図1" fo:content-width="5in" src="/files/ftp_upload/51820/51820fig1highres.jpg" width="500" /> 図1： </strong<html> &gt; すべての適切な寸法のU字型のプラスチックステージと収集スポンジの Cのアートゥーン表現。10cmの距離は、幼若ラットを確保するために、コレクションスポンジとプラスチックステージの上面との間に維持されなければならない180を完了するのに十分な時間がある°回転。 <img alt="図2" fo:content-width="5in" src="/files/ftp_upload/51820/51820fig2highres.jpg" width="500" /> 図2：傷害誘導プラットフォームの（A）写真表現。ヘッドが直接落錘以下になるように幼若ラットを獲得スズ箔上の胸ダウンに配置される。傷害誘導プラットフォームの（B）側面図。MTBIの誘導に使用される量（C）写真デモ。 アップロード/ 51820 / 51820fig3highres.jpg &quot;幅=&quot; 500 &quot;/&gt; 図3：MTBIの出品に有意な増加を受けているシングルMTBIと偽の負傷を経験した若年ラット（* P &lt;0.01）ラットを経験した時から右への幼若ラットの間での平均の違いのグラフィカル表現仰臥位から​​身を正すのに必要な時間の長さ。 <img alt="図4" fo:content-width="5in" src="/files/ftp_upload/51820/51820fig4highres.jpg" width="500" /> 図4：シングルMTBIと偽の負傷を経験した若年ラット（* p &lt;0.05）を経験した若年ラットによるビームウォーキングタスクに展示後肢足-スリップの平均数のグラフ表示。

Watch this Scientific Journal Video about A Novel Model of Mild Traumatic Brain Injury for Juvenile Rats at JoVE.com

A Novel Model of Mild Traumatic Brain Injury for Juvenile Rats

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.

少年ラット用マイルド外傷性脳損傷の新規モデル

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

a-novel-model-of-mild-traumatic-brain-injury-for-juvenile-rats

Research

JoVE Journal

Medicine

23.4K ビュー.  University of Calgary. 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. 

ビデオ: A Novel Model of Mild Traumatic Brain Injury for Juvenile Rats

Acute and Chronic Tactile Sensory Testing after Spinal Cord Injury in Rats

Spinal cord injury (SCI) impairs sensory systems causing allodynia1-8. To identify cellular and molecular causes of allodynia, sensitive and valid sensory testing in rat SCI models is needed. However, until recently, no single testing approach had been validated for SCI so that standardized methods have not been implemented across labs. Additionally, available testing methods could not be implemented acutely or when severe motor impairments existed, preventing studies of the development of SCI-induced allodynia3. Here we present two validated sensory testing methods using von Frey Hair (VFH) monofilaments which quantify changes in tactile sensory thresholds after SCI4-5. One test is the well-established Up-Down test which demonstrates high sensitivity and specificity across different SCI severities when tested chronically5. The other test is a newly-developed dorsal VFH test that can be applied acutely after SCI when allodynia develops, prior to motor recovery4-5. Each VFH monofilament applies a calibrated force when touched to the skin of the hind paw until it bends. In the up-down method, alternating VFHs of higher or lower forces are used on the plantar L5 dermatome to delineate flexor withdrawal thresholds. Successively higher forces are applied until withdrawal occurs then lower force VFHs are used until withdrawal ceases. The tactile threshold reflects the force required to elicit withdrawal in 50% of the stimuli. For the new test, each VFH is applied to the dorsal L5 dermatome of the paw while the rat is supported by the examiner. The VFH stimulation occurs in ascending order of force until at least 2 of 3 applications at a given force produces paw withdrawal. Tactile sensory threshold is the lowest force to elicit withdrawal 66% of the time. Acclimation, testing and scoring procedures are described. Aberrant trials that require a retest and typical trials are defined. Animal use was approved by Ohio State University Animal Care and Use Committee.

We describe two tactile sensory testing methods for acute or chronic periods of spinal cord injury in rats. These validated procedures can detect the development and maintenance of allodynia-like sensations.

ラット脊髄損傷後の急性および慢性の触覚官能検査

Spinal cord injury (SCI) impairs sensory systems causing allodynia1-8. To identify cellular and molecular causes of allodynia, sensitive and valid sensory ...

医学

A Contusion Model of Severe Spinal Cord Injury in Rats

The translational potential of novel treatments should be investigated in severe spinal cord injury (SCI) contusion models. A detailed methodology is described to obtain a consistent model of severe SCI. Use of a stereotactic frame and computer controlled impactor allows for creation of reproducible injury. Hypothermia and urinary tract infection pose significant challenges in the post-operative period. Careful monitoring of animals with daily weight recording and bladder expression allows for early detection of post-operative complications. The functional results of this contusion model are equivalent to transection models. The contusion model can be utilized to evaluate the efficacy of both neuroprotective and neuroregenerative approaches.

A contusion model of severe spinal cord injury is described. Detailed pre-operative, operative and post-operative steps are described to obtain a consistent model.

ラットにおける重度の脊髄損傷挫傷モデル

The translational potential of novel treatments should be investigated in severe spinal cord injury (SCI) contusion models. A detailed methodology is ...

A Novel Vertebral Stabilization Method for Producing  Contusive Spinal Cord Injury

Clinically-relevant animal cervical spinal cord injury (SCI) models are essential for developing and testing potential therapies; however, producing reliable cervical SCI is difficult due to lack of satisfactory methods of vertebral stabilization. The conventional method to stabilize the spine is to suspend the rostral and caudal cervical spine via clamps attached to cervical spinous processes. &#160;However, this method of stabilization fails to prevent tissue yielding during the contusion as the cervical spinal processes are too short to be effectively secured by the clamps (Figure 1). &#160;Here we introduce a new method to completely stabilize the cervical vertebra at the same level of the impact injury. &#160;This method effectively minimizes movement of the spinal column at the site of impact, which greatly improves the production of consistent SCIs. &#160;We provide visual description of the equipment (Figure 2-4), methods, and a step-by-step protocol for the stabilization of the cervical 5 vertebra (C5) of adult rats, to perform laminectomy (Figure 5) and produce a contusive SCI thereafter. &#160;Although we only demonstrate a cervical hemi-contusion using the NYU/MASCIS impactor device, this vertebral stabilization technique can be applied to other regions of the spinal cord, or be adapted to other SCI devices. &#160;Improving spinal cord exposure and fixation through vertebral stabilization may be valuable for producing consistent and reliable injuries to the spinal cord. &#160;This vertebral stabilization method can also be used for stereotactic injections of cells and tracers, and for imaging using two-photon microscopy in various neurobiological studies.

Vertebral stabilization is necessary for minimizing variability, and for producing consistent experimental spinal cord injuries.&#160; Using a customized stabilizing apparatus in conjunction with the NYU/MASCIS impactor device, we have demonstrated here the proper equipment and procedure for generating reproducible hemi-contusive cervical (C5) spinal cord injuries in adult rats.

挫傷、脊髄損傷の新規な製造脊椎安定化法

Clinically-relevant animal cervical spinal cord injury (SCI) models are essential for developing and testing potential therapies; however, producing ...

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.

として脳微小血管内皮細胞（CEND）でストレッチ<em&gt;インビトロ</em血液脳関門の&gt;外傷性脳損傷モデル

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

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.

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.

外傷性脳損傷のための制御皮質衝撃モデル

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

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.

腎臓虚血再灌流障害：障害のマウスモデルおよび再生

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 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.

マウスにおける組織変位ベースの脊柱挫傷モデルの検討

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.

片性および反復性軽度外傷性脳損傷のマウスモデル

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 ...

Spinal Cord Lateral Hemisection and Asymmetric Behavioral Assessments in Adult Rats

Incomplete spinal cord injury (SCI) often leads to impairments of sensorimotor functions and is clinically the most frequent type of SCI. Human Brown-S&#233;quard syndrome&#160;is a common type of incomplete SCI caused by a lesion to one half of the spinal cord which results in paralysis and loss of&#160;proprioception&#160;on the same (or ipsilesional) side as the injury, and loss of pain and temperature sensation on the opposite (or contralesional) side. Adequate methodologies for producing a spinal cord lateral hemisection (HX) and assessing neurological impairments are essential to establish a reliable animal model of Brown-S&#233;quard syndrome. Although lateral hemisection model plays a pivotal role in basic and translational research, standardized protocols for creating such a hemisection and assessing unilateralized function are lacking. The goal of this study is to describe step-by-step procedures to produce a rat spinal lateral HX at the 9th thoracic (T9) vertebral level. We, then, describe a combined behavior scale for HX (CBS-HX) that provides a simple and sensitive assessment of asymmetric neurological performance for unilateral SCI. The CBS-HX, ranging from 0 to 18, is composed of 4 individual assessments which include unilateral hindlimb stepping (UHS), coupling, contact placing, and grid walking. For CBS-HX, the ipsilateral and contralateral hindlimbs are assessed separately. We found that, after a T9 HX, the ipsilateral hindlimb showed impaired behavior function whereas the contralateral hindlimb showed substantial recovery. The CBS-HX effectively discriminated behavioral functions between ipsilateral and contralateral hindlimbs and detected temporal progression of recovery of the ipsilateral hindlimb. The CBS-HX components can be analyzed separately or in combination with other measures when needed. Although we only provided visual descriptions of the surgical procedures and behavioral assessments of a thoracic HX, the principle may be applied to other incomplete SCIs and at other levels of the injury.

Here we describe surgical procedures to produce a reliable spinal cord lateral hemisection (HX) at the 9th thoracic level in adult rats and neurobehavioral assessments designed for detecting asymmetric deficits after such a unilateral injury.

成人ラットにおける脊髄横片切と非対称行動評価

Incomplete spinal cord injury (SCI) often leads to impairments of sensorimotor functions and is clinically the most frequent type of SCI. Human ...

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.

重症脳損傷患者 [18F] FDG トレーサーを用いた定量的評価

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