Name: isolating myofibrils from skeletal muscle biopsies and determining contractile function with a nano-newton resolution force transducer
Uploaded: 2020-05-07T14:00:00
Description: Watch this Scientific Journal Video about Isolating Myofibrils from Skeletal Muscle Biopsies and Determining Contractile Function with a Nano-Newton Resolution Force Transducer at JoVE.com

该项目由AFM-Telethon和Nemaline Myopath基金会建设力量资助。作者希望承认本文中提到的产品的创建者 IONOptix Inc.

获得人类活检的议定书由VU大学医学中心机构审查委员会（#2014/396）批准，并获得受试者的书面知情同意。获得动物肌肉活检的议定书得到了VU大学当地动物伦理委员会（AVD114002016501）的批准。
1. 准备和肌黄种人隔离
注：使用前面描述的方法甘油活检，准备不同的钙浓度（pCa）溶液7,7，16，17，,<sup class="x...

<ol>
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E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+increase+in+non-cross-bridge+forces+after+stretch+of+activated+striated+muscle+is+related+to+titin+isoforms.">The increase in non-cross-bridge forces after stretch of activated striated muscle is related to titin isoforms.</a> American Journal of Physiology - Cell Physiology. 310, 19-26 (2016).</li><li>Labuda, A., Brastaviceanu, T., Pavlov, I., Paul, W., Rassier, D. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optical+detection+system+for+probing+cantilever+deflections+parallel+to+a+sample+surface.">Optical detection system for probing cantilever deflections parallel to a sample surface.</a> Review of Scientific Instruments. 82, 013701 (2011).</li><li>Chavan, 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=Ferrule-top+nanoindenter:+an+optomechanical+fiber+sensor+for+nanoindentation.">Ferrule-top nanoindenter: an optomechanical fiber sensor for nanoindentation.</a> Review of Scientific Instruments. 83, 115110 (2012).</li><li>Beekmans, S. V., Iannuzzi, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+metrological+approach+for+the+calibration+of+force+transducers+with+interferometric+readout.">A metrological approach for the calibration of force transducers with interferometric readout.</a> Surface Topography: Metrology and Properties. 3, (2015).</li><li>van Hoorn, H., Kurniawan, N. A., Koenderink, G. H., Iannuzzi, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Local+dynamic+mechanical+analysis+for+heterogeneous+soft+matter+using+ferrule-top+indentation.">Local dynamic mechanical analysis for heterogeneous soft matter using ferrule-top indentation.</a> Soft Matter. 12, 3066-3073 (2016).</li><li>Winter, J. 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=KBTBD13+is+an+actin-binding+protein+that+modulates+muscle+kinetics.">KBTBD13 is an actin-binding protein that modulates muscle kinetics.</a> Journal of Clinical Investigation. , (2019).</li><li>Winter, J. 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=Mutation-specific+effects+on+thin+filament+length+in+thin+filament+myopathy.">Mutation-specific effects on thin filament length in thin filament myopathy.</a> Annals of Neurology. 79, 959-969 (2016).</li><li>Ottenheijm, C. A. C., 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=Deleting+exon+55+from+the+nebulin+gene+induces+severe+muscle+weakness+in+a+mouse+model+for+nemaline+myopathy.">Deleting exon 55 from the nebulin gene induces severe muscle weakness in a mouse model for nemaline myopathy.</a> Brain. 136, 1718-1731 (2013).</li><li>Ribeiro, P. 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=Contractility+of+myofibrils+from+the+heart+and+diaphragm+muscles+measured+with+atomic+force+cantilevers:+effects+of+heart-specific+deletion+of+arginyl-tRNA-protein+transferase.">Contractility of myofibrils from the heart and diaphragm muscles measured with atomic force cantilevers: effects of heart-specific deletion of arginyl-tRNA-protein transferase.</a> International Journal of Cardiology. 168, 3564-3571 (2013).</li><li>Pinniger, G. J., Bruton, J. D., Westerblad, H., Ranatunga, K. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+a+Myosin-II+Inhibitor+(N-benzyl-p-toluene+Sulphonamide,+BTS)+on+Contractile+Characteristics+of+Intact+Fast-twitch+Mammalian+Muscle+Fibres.">Effects of a Myosin-II Inhibitor (N-benzyl-p-toluene Sulphonamide, BTS) on Contractile Characteristics of Intact Fast-twitch Mammalian Muscle Fibres.</a> Journal of Muscle Research and Cell Motililty. 26, 135-141 (2005).</li><li>Stehle, R., Kr&#252;ger, M., Pfitzer, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Force+kinetics+and+individual+sarcomere+dynamics+in+cardiac+myofibrils+after+rapid+Ca(2+)+changes.">Force kinetics and individual sarcomere dynamics in cardiac myofibrils after rapid Ca(2+) changes.</a> Biophysics Journal. 83, 2152-2161 (2002).</li><li>Najafi, 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=End-diastolic+force+pre-activates+cardiomyocytes+and+determines+contractile+force:+role+of+titin+and+calcium.">End-diastolic force pre-activates cardiomyocytes and determines contractile force: role of titin and calcium.</a> Journal of Physiology. 597, 4521-4531 (2019).</li></ol>

描述是一种协议，用于评估从人或动物骨骼肌组织中分离出的肌骨的收缩功能。查万等人之前曾描述过这种装置的力分辨率。简言之，它由检测纤维和悬臂之间形成的Fabry-Pérot腔长度的随机波动决定，这些空腔产生读出输出（以V表示）时噪声的主导部分，乘以偏转灵敏度（以m/V表示）和悬臂的弹簧常数（以N/m表示），从而产生力噪声。在我们的设置中，在读出输出时，在 1，000 ...

条纹肌肉细胞是日常生活活动不可缺少的。肢体运动、呼吸功能和心脏的泵送运动依赖于肌肉细胞产生的力。骨骼肌由包含一束单肌肉纤维的肌肉分册组成（图1A）。这些肌肉纤维由肌纤维组成，由连续连接的沙球组成（图1B，D）。沙康鱼含有薄而厚的细丝。这些主要由活性素和米奥辛分子链组成（图1B）。行为-肌素相互作用负责肌肉的产生力的能力。编码为沙康蛋白的基因突变的患者，如内布林、奥平和肌蛋白T，由于收缩功能障碍1而出现肌肉无力。
肌肉收缩的质量可以在组织的各个层面研究，从体内整个肌肉到体外运动性测定中的行为-肌素相互作用。在过去的几十年里，几个研究小组已经开发出一些装置，以确定个体肌黄种人,2，3，4，5，6，7，8，9，103,7,8,9,的合同性。4,5,62这些设置基于检测由肌黄种枪收缩引起的悬臂（即光束偏转）的激光偏转变化（详情见 Labuda 等人11）。虽然确定肌黄体联的收缩函数有一些局限性（例如，在肌黄种体上游的激励-收缩耦合过程的动态是缺乏的），但这种方法具有多种优点。其中包括：1） 在沙康人几何约束的情况下评估行为-明辛相互作用的能力;2） 评估行为-肌素相互作用的能力，而不对受损的相邻肌纤维的潜在混淆影响（当测量单肌肉纤维超结构损伤和肌纤维错位时，可能导致收缩性受损）（图1D）;3） 肌纤维的小直径（±1 μm，图2A）和缺乏膜允许几乎瞬间钙扩散到沙状物。此外，如果肌黄种人存在结构损伤，它们很可能在隔离期间或实验期间断裂。因此，评估肌纤维收缩是研究肌肉收缩的基本机制，并了解干扰行为-肌蛋白相互作用是否是由沙康蛋白突变引起的肌肉疾病的主要原因的优雅方法。
该协议提出了一个新开发的设置，以确定肌纤维的收缩性，其中结合了具有纳米牛顿分辨率的悬臂力探头（即Opiforce）。该力探针基于干涉测量原理。干涉测量允许使用相对僵硬的直性插性。这使得测量力与悬臂的小偏转，接近等轴测收缩的肌醇。该探头允许评估低被动和主动力，由从不同的肌肉活检分离出的单个肌黄素和主动力，包括来自人类受试者的活检，具有很高的信号与噪声比。此设置中集成的光学悬臂力探头基于 Fabry-Pérot 干涉仪12。干涉仪可检测光纤与安装在铁杉上的镀金悬臂之间的小位移（图3）。光纤和悬臂之间的间隙称为法布里-佩罗腔。使用两种胶涂层玻璃安装纤维安装在探头和压电电机之间。肌异的力可以从干涉仪数据中数学上产生。干涉测量基于两个或两个多波的叠加或干扰（在此设置中，三个光波）。波长在 1，528.77~1，563.85 nm 之间的激光从干涉仪发射并通过光纤发送。在探头中，光在光纤和介质之间的接口上反射1（图3A）;2） 在介质和悬臂的接口（图3B）;和3）在悬臂的金属和黄金涂层之间的接口（图3C）。接口 A 和 B 上的反射取决于探头被淹没介质的折射率 （n）。光线由三个叠加反射组成，返回干涉仪中的光电二极管。光电二极管测量光的强度，这是三个叠加反射的干扰模式的结果。当通过激活或拉伸肌黄种人产生收缩力时，肌骨力会拉上悬臂。此运动更改型腔大小（d）， 因此更改适合型腔的波长数。悬臂反射的光将具有不同的相位，从而产生不同的干扰模式。光电二极管将干扰模式强度的这种变化记录为伏特的变化。随后，考虑到悬臂刚度，根据这种变化计算了肌黄热化力生成。力探针由制造商通过推动安装针的尖端，连接到悬臂的自由手端，对称量秤，同时保持悬臂的弯曲等于读出激光13波长的倍数。因此，干涉测量是一种高度敏感的方法，用于检测距离的小变化，从而能够测量纳米牛顿分辨率的力。此分辨率能够评估具有高信噪比的 myofibrillar 力生产。虽然传统的干涉测量将测量范围限制在干涉曲线的线性部分，但使用锁定放大器和激光波长调制克服了这一限制14。这一点在讨论部分进行了更详细的解释。
为了测量肌磷气活性张力，采用了快速灌注系统，使肌磷酸化液暴露在钙溶液中（图4A）。快速步进灌注系统可在 10 ms 内进行溶液更改。由于其直径小，钙扩散到肌磷几乎瞬间。因此，该系统特别适合测量激活期间和放松期间释放的机蛋白-明蛋白结合率。激活速率 （kACT）和松弛 （kREL） 可以从激活松弛曲线中确定。此外，通过将肌磷暴露给浓度增加的钙溶液，可以确定力-钙关系和钙敏感性。
此外，压电长度电机能够快速拉伸和缩短肌黄种人。这提供了研究肌黄油的粘弹性特性（即被动张力）的可能性，以及执行快速缩短和重新拉伸的肌黄油，以确定张力重建的速度（kTR）。从主动和被动张力实验中检索到的参数可以通过沙康蛋白中的基因突变来改变。
此定制设置用于测量与健康人、患者和小鼠骨骼肌分离的肌纤维的主动和被动收缩特性。

<table>
	<tbody>
		<tr>
			<td>Bio Spec Products, Inc.</td>
			<td>985370-XL</td>
			<td>To isolate myofibrils</td>
			<td></td>
		</tr>
		<tr>
			<td>Custom coded</td>
			<td></td>
			<td>Matlab</td>
			<td></td>
		</tr>
		<tr>
			<td>Custom fabricated</td>
			<td></td>
			<td>Includes Labview program to control over serial connection; To control valves</td>
			<td></td>
		</tr>
		<tr>
			<td>Custom fabricated</td>
			<td></td>
			<td>To cool the Peltier module</td>
			<td></td>
		</tr>
		<tr>
			<td>Custom fabricated</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Custom fabricated</td>
			<td></td>
			<td>Aluminum tissue chamber</td>
			<td></td>
		</tr>
		<tr>
			<td>Custom fabricated</td>
			<td></td>
			<td>To control the valves; Includes PC software to control over USB</td>
			<td></td>
		</tr>
		<tr>
			<td>IonOptix</td>
			<td></td>
			<td>System controller software: data recording software with advanced signal generator for piezo and fast-step</td>
			<td></td>
		</tr>
		<tr>
			<td>IonOptix</td>
			<td>MCS100</td>
			<td>To record sarcomere length</td>
			<td></td>
		</tr>
		<tr>
			<td>IonOptix</td>
			<td></td>
			<td>Includes: Optiforce (interferometer), Micromanipulators, Signal interface, Piezo motor and controller. Based on the MyoStretcher</td>
			<td></td>
		</tr>
		<tr>
			<td>IonOptix</td>
			<td></td>
			<td>Force probe</td>
			<td></td>
		</tr>
		<tr>
			<td>Koolance</td>
			<td>ADT-EX004S</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Koolance</td>
			<td>EX2-755</td>
			<td>To cool the Peltier module</td>
			<td></td>
		</tr>
		<tr>
			<td>Microsoft</td>
			<td></td>
			<td>Data registration</td>
			<td></td>
		</tr>
		<tr>
			<td>Olympus</td>
			<td>IX71</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Olympus</td>
			<td>TH4-200</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Sigma-Aldrich</td>
			<td>529265</td>
			<td>Poly(2-hydroxyethyl methacrylate); Coating for microscope slides to prevent sticking of tissue</td>
			<td></td>
		</tr>
		<tr>
			<td>Sigma-Aldrich</td>
			<td>78471</td>
			<td>Crystals to dissolve in ethanol resulting in glue</td>
			<td></td>
		</tr>
		<tr>
			<td>TE Technology, Inc.</td>
			<td>TE-63-1.0-1.3</td>
			<td>To cool the tissue flow chamber</td>
			<td></td>
		</tr>
		<tr>
			<td>TE Technology, Inc.</td>
			<td>TC-720</td>
			<td>Includes PC software to control over USB</td>
			<td></td>
		</tr>
		<tr>
			<td>Tecan Trading AG</td>
			<td>20736652</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Tecan Trading AG</td>
			<td>20739263</td>
			<td>Syringe pump to induce backgroundflow together with fast-step perfusion system; Outflow from tissue flow chamber</td>
			<td></td>
		</tr>
		<tr>
			<td>Thermo scientific</td>
			<td>2441081</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Warner Instruments (Harvard Bioscience, Inc.)</td>
			<td>Discontinued</td>
			<td>Alternative: SF-77CST/VCS-77CSP</td>
			<td></td>
		</tr>
		<tr>
			<td>Warner Instruments (Harvard Bioscience, Inc.)</td>
			<td>TG150-4</td>
			<td>To perfuse the tissue</td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td>1 PC for IonWizard and 1 PC for other software</td>
			<td></td>
		</tr>
	</tbody>
</table>

isolating myofibrils from skeletal muscle biopsies and determining contractile function with a nano-newton resolution force transducer

条纹肌肉细胞对于人类和动物的活动是必不可少的。单肌肉纤维由肌纤维组成，由连续相连的沙康鱼组成，这是肌肉中最小的收缩单位。沙康功能障碍导致沙康蛋白编码基因突变的患者肌肉无力。对肌磷酸酯力学的研究允许在测量单肌肉纤维的收缩性时，评估行为素-肌素相互作用，而不会产生受损、相邻的肌纤维的潜在混淆效应。肌黄体的极端结构损伤和错位可能导致收缩受损。如果肌黄热动物存在结构损伤，则在隔离过程中或实验期间，它们可能会断裂。此外，在肌磷动物的研究提供了在沙康的几何约束存在的情况下对行为-肌素相互作用的评估。例如，肌纤维的测量可以阐明肌纤维功能障碍是否是沙康蛋白突变的主要影响。此外，由于肌黄磷的直径小，钙溶液或化合物的灌注几乎是瞬间的。这使得肌黄种人非常适合测量力生产期间的激活和放松率。本文所述的协议采用基于法布里-佩罗特干涉仪原理的光学力探头，该干涉仪能够测量纳米牛顿范围内的力，并结合压电长度电机和快速步进灌注系统。此设置使肌黄种力力学能够研究高分辨率力测量。

使用系统控制器软件记录并打开数据跟踪（ 参见材料表）。将完整的跟踪或选定的段导出到剪贴板或文本文件，以使用所需的软件进行进一步分析。使用自定义软件或手动切换用于控制不同解决方案流量的阀门。自定义 MATLAB 脚本用于分析激活、张力重新生成和放松的速率。被动力实验的最大主动力和峰值及高原力直接取自系统控制器软件力轨迹。安装肌黄种人（图2?...

Watch this Scientific Journal Video about Isolating Myofibrils from Skeletal Muscle Biopsies and Determining Contractile Function with a Nano-Newton Resolution Force Transducer at JoVE.com

Isolating Myofibrils from Skeletal Muscle Biopsies and Determining Contractile Function with a Nano-Newton Resolution Force Transducer

此处介绍的是一个协议，用于评估具有纳米-牛顿分辨率的条纹肌肉肌异半孔的收缩特性。该协议采用基于干涉测量的光学力探头的设置。此设置生成具有高信噪比的数据，并可评估 myofibril 的收缩动力学。

使用纳米-牛顿分辨率力转换器从骨骼肌肉活检中隔离肌异物并确定收缩函数

Striated muscle cells are indispensable for the activity of humans and animals. Single muscle fibers are comprised of myofibrils, which consist of ...

评估从条纹肌肉分离出的肌异体体收缩特性可用于确定沙康利功能障碍是否是由于沙康蛋白突变导致肌肉无力的主要原因。该技术可用于获取具有非常高信噪比的数据，具有纳米新分辨率。该协议也适合测量渗透性心肌细胞的收缩性。请记住，力传感器非常脆弱。因此，当从安装针上去除胶水或粘合肌黄素时，你需要有一个稳定的手，大量的练习，和大量的耐心。在安装组织之前，在含有肌肉组织的管子中放置一个均质棒。保持管子在冰上，旋转转子15秒的速度5。在均质结束时，将产生的肌黄纤维悬浮液的 50 微升和 250 微升的放松溶液转移到组织浴中的多 HEMA 涂层幻灯片上。用盖子盖住浴缸，保护混合物免受灰尘的污染，并等待 5 到 10 分钟，让肌黄油沉入落水底部。在灭菌过程中，在65摄氏度下加热Shellac乙醇胶30至60秒，然后将大约6微升胶水加入未涂覆的玻璃滑梯上。反复将每个安装针的尖端浸入胶水中，直到可见一层胶水。然后使用微机械器垂直移动探头和压电，为显微镜舞台上的组织浴提供空间，并去除含有胶水的玻璃幻灯片。安装肌纤维后，测量沙壳长度，移动压电和/或力探头，将肌黄纤维的初始沙壳长度设置为 2.5 微米。利用系统控制器软件的容器功能，测量肌黄热气的长度和宽度。使用显微镜舞台将肌黄油放在视频图像的中心，将矩形从肌黄油的一侧拉伸到另一侧，注意包括胶滴的暗边。要开始记录数据，请单击"开始"。五秒钟后，单击"暂停"。长度将被记录。要测量宽度，请旋转摄像机 90 度以查看肌或气本身边缘的对比度。调整矩形并单击"开始"开始开始记录数据。五秒钟后，单击"暂停"。宽度将被记录。要定位玻璃，请使用目镜和操纵器小心地将塔玻璃向肌纤维。将玻璃的顶部通道与肌纤维对齐，并执行快速步骤以检查位置。打开背景放松流以检查塔玻璃对齐，并使用 Luer 阀杆打开流室的流入。然后开始排空流气室，防止流室溢出，将流出泵阀设置为浴阀二，微步模式为微，柱塞目标为48000，柱塞速度为38至40。要测量张力重建的速率，计算将肌黄二百里松弛 15%所需的压电运动，然后将此值输入信号发生器。单击"恢复"以继续记录数据并打开阀门 1 和 6，分别启动放松溶液和不同钙浓度流。选择干涉仪上的复位范围以重置干涉仪的范围，使基准力为零伏特。当力轨迹稳定时，执行 100 微米步长的塔玻璃快速步进。当达到力高原时，使用压电力执行缩短的重新拉伸。将记录激活松弛跟踪。单击"暂停"。要执行步进拉伸，请单击"启动"并重置干涉仪的范围，以便基准力为零伏特。使用信号发生器执行分步拉伸。拉伸完成后，使用压电将肌黄种轮缩短到松弛长度。然后按暂停并停止并保存数据。在这里，从健康的人类四头肌分离出的肌骨力实验的力痕迹显示。肌异物被激活五次，溶液的钙浓度不同，平均最大力为每平方毫米约123毫纽顿。在五条钙曲线中，每次激活时，高原力的力钙浓度曲线的构造允许计算钙浓度在最大力产生量的 50% 。如此代表性分析所示，在单个实验中，用多种化合物处理肌黄体，以回答有关肌黄体菌型的其他问题。也可以测量主动力和沙康长度，以便计算重建、激活和放松的速率。点状红色框中显示的陡峭上升是由粘度和弹性引起的。高原只像弹性成分。由于粘度线性抵抗应变，因此在去除应变后力下降。定位玻璃时，请确保将其与肌纤维正确对齐。否则，激活解决方案可能介于力探针的光纤和悬臂之间，这会导致数据中出现伪影。此外，肌黄种人可能无法正确激活。这种灌注方法也适合确定肌纤维类型的肌纤维类型。例如，您可以先用正常的钙溶液来灌注肌纤维，然后加入肌肉纤维型特异性增强力化合物。

Research

JoVE Journal

Biology

Adult and Embryonic Skeletal Muscle Microexplant Culture and Isolation of Skeletal Muscle Stem Cells

成人和胚胎骨骼的肌肉Microexplant文化和骨骼肌肉干细胞的分离

Cultured embryonic and adult skeletal muscle cells have a number of different uses. The micro-dissected explants technique described in this chapter is a ...

科研

生物学

Mitochondrial Isolation from Skeletal Muscle

骨骼肌的线粒体分离

Mitochondria are organelles controlling the life and death of the cell. They participate in key metabolic reactions, synthesize most of the ATP, and ...

Purification of Progenitors from Skeletal Muscle

纯化的骨骼肌的先觉者

Skeletal muscle contains multiple progenitor populations of distinct embryonic origins and developmental potential. Myogenic progenitors, usually residing ...

Procedures for Rat in situ Skeletal Muscle Contractile Properties

Procedures for Rat in situ Skeletal Muscle Contractile Properties

对大鼠的过程<em在原位</em骨骼肌收缩性能

There are many circumstances where it is desirable to obtain the contractile response of skeletal muscle under physiological circumstances: normal ...

Isolation and Culture of Individual Myofibers and their Satellite Cells from Adult Skeletal Muscle

单个肌纤维和成人骨骼肌卫星细胞的分离和培养

Muscle  regeneration in the adult is performed by resident stem cells called satellite  cells. Satellite cells are defined by  their position between the ...

Force Measurement During Contraction to Assess Muscle Function in Zebrafish Larvae

在收缩力测量评估肌肉功能在斑马鱼幼虫

Zebrafish larvae provide models of muscle development, muscle disease and muscle-related chemical toxicity, but related studies often lack functional ...

Isolation of Intact Mitochondria from Skeletal Muscle by Differential Centrifugation for High-resolution Respirometry Measurements

骨骼肌完整的线粒体的分离差速离心高分辨率测量呼吸运动

Mitochondria are involved in cellular energy metabolism and use oxygen to produce energy in the form of adenosine triphosphate (ATP). Differential ...

Immunolabelling Myofiber Degeneration in Muscle Biopsies

肌肉活检中的免疫标记肌纤维退化

The necrosis of muscle fibres (myonecrosis) plays a central role in the pathogenesis of several muscle conditions, including muscular dystrophies. ...

Isolation and Characterization of Exosomes from Skeletal Muscle Fibroblasts

骨骼肌成纤维细胞外泌体的分离和表征

Exosomes are small extracellular vesicles released by virtually all cells and secreted in all biological fluids. Many methods have been developed for the ...

Collection of Skeletal Muscle Biopsies from the Superior Compartment of Human Musculus Tibialis Anterior for Mechanical Evaluation

从人类肌肉提比利斯前部高级隔间收集骨骼肌肉活检，用于机械评估

The mechanical properties of contracting skeletal fibers are crucial indicators of overall muscle health, function, and performance. Human skeletal muscle ...