作者感谢博士。詹姆斯·霍金斯，祖熙玉和禤去从国家心脏，肺和血液研究所（NHLBI）为他们的鼠标手术准备和石蜡切片染色的援助。作者感谢美国国立卫生研究院研究员编委会的编辑协助。

所有小鼠实验用协议号H0083R3批准的动物护理和使用计划，在美国国立卫生研究院（NIH）。本NHLBI IACUC认可无镇痛药的协议。 1.低温麻醉新生小鼠<ol><li>手术前消毒海绵和手术设备中的高压釜中。准备所有的手术材料和在加热珠灭菌15-20分钟切换提前达到240℃至270℃。 </li><li>传输所有C57BL / 6幼鼠（年龄P1）从哺乳的母亲到一个干净的鼠笼新鲜的床上用品和筑巢的材料。一旦幼仔取入手术室，迅速地进行根尖手术，以减少他们的花费的时间从母亲分离并降低产妇拆的风险。 </li><li>将海绵在冰床上，然后将一只小狗在海绵〜3分钟，实现低温麻醉。通过观察AP确认麻醉NEA和运动不能和捏一个后脚。检查新生儿的状态经常因为时间太少不会让小狗动性和呼吸暂停，和麻醉的时间过多会降低成活率12。 </li></ol> 2.开胸<ol><li>传送从冰床的小狗到外科台式区域，使用胶带来固定其手臂，腿和尾部在仰卧位置。 </li><li>消毒胸部用聚维酮碘，轻轻地用70％酒精消毒片进行清洁。 </li><li>做一个横向的皮肤切口，沿胸腔使用Vannas弹簧剪刀脚的第四肋间区域，然后生硬剖析第四肋间肌肉，以方便进入心脏。 注:生存率提高时，在手术过程中尽量减少失血。 </li></ol>心脏心室心尖3.手术截肢<ol><li>用手，轻轻涂抹于腹部压力exteriorize的顶点的心脏。吸收周围的血用无菌棉签涂抹清晰的可视化手术区。对于假手术对照新生儿，直接进入步骤4（缝合和恢复小鼠）。 </li><li>在放大镜灯，并使用虹膜切除术剪刀，直到低压室暴露轻轻地进行零碎切除左心室（LV）的。要小心，尽量减少LV的切除部分。大约15％的切除是必要实现低压室的最佳曝光。 </li><li>确保心脏返回到胸腔，一旦低压室暴露。 </li></ol> 4.缝合和小鼠恢复<ol><li>缝合肋和肌肉一起使用无菌脯氨酸6-0缝线以密封胸腔，然后用皮胶小心关闭皮肤切口部位。 </li><li>暖新生儿下为〜3分钟为恢复一加热灯，然后用70％的酒精消毒片befo清洁血液和胶的痕迹重新它重新引入到其同窝。尝试完成整个手术过程在10分钟内，因为减少花费从母体分离的时间，从而提高根尖切除后的小狗存活。 </li><li>以下各手术中，将手术工具与热珠灭菌的珠子接触，用于完全灭菌约20秒。允许外科工具，以各术前冷却至室温。 </li><li>完成手术的所有幼仔在产仔后，他们回到母亲的窝前将与母亲的床上用品和排泄物的幼崽。 注:一般情况下，ICR / CD-1小鼠是更好的养母不是C57BL / 6，但即使在相同的遗传背景的乳母，促进本能而有所不同。如果改变一个哺乳的母亲需要通过母体拆，以减少死亡率，取出P0幼崽哺乳的母亲，然后在P1进行根尖切除术。只有执行下列任一假手术或根尖řesection于幼崽一窝，因为混合假和手术的幼崽可以降低手术组幼崽6的存活率。 </li></ol> 5.后外科分析<ol><li>手术后的第二天，监视幼崽，确保有假和手术组间无差异，并计算幼仔的数量来衡量的存活率。如果手术被适当地进行时，存活率应当是在两个假和手术组中是相似和大于60％。 </li><li>心脏隔离和固定。 <ol><li>安乐死的幼崽在天1，并通过斩首和21日手术后2术后通过CO2的死亡颈椎脱位的保证，然后用70％的酒精准备擦拭胸部。 </li><li>切开胸部正中线皮肤和肌肉，然后打开箱子。 </li><li>消费税从胸腔整个心灵和修复5毫升4％多聚甲醛O / N在室温每个样本的整个心脏。 </li></ol></li><li>在第二天，转样本以70％的乙醇。样品可以存储最多一周石蜡包埋之前。 </li><li>片通过整个心室5-μm厚的石蜡切片，进行标准苏木精和曙红（H＆E）和Masson三色染色以检查再生反应5,7，具体而言，H＆E染色用于检查肌肉更换和马松三色染色用于研究纤维化反应5。 </li><li>选择感兴趣的区域，并设置了每个样品的至少三个焦点手动使用的滑动扫描器。图像，并根据制造商的使用默认参数的指令分析染色载玻片在40×放大率。 </li></ol>

<ol>
	<li>Lin, Z., Pu, W. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Strategies+for+cardiac+regeneration+and+repair.">Strategies for cardiac regeneration and repair.</a> Sci Transl Med. 6, 231-239 (2014).</li><li>Xin, M., Olson, E. N., Bassel-Duby, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mending+broken+hearts:+cardiac+development+as+a+basis+for+adult+heart+regeneration+and+repair.">Mending broken hearts: cardiac development as a basis for adult heart regeneration and repair.</a> Nat Rev Mol Cell Biol. 14, 529-541 (2013).</li><li>Mahmoud, A. I., Porrello, E. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Turning+back+the+cardiac+regenerative+clock:+lessons+from+the+neonate.">Turning back the cardiac regenerative clock: lessons from the neonate.</a> Trends Cardiovasc Med. 22, 128-133 (2012).</li><li>Porrello, E. R., Olson, E. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+neonatal+blueprint+for+cardiac+regeneration.">A neonatal blueprint for cardiac regeneration.</a> Stem Cell Res. 13, 556-570 (2014).</li><li>Porrello, E. R., 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=Transient+regenerative+potential+of+the+neonatal+mouse+heart.">Transient regenerative potential of the neonatal mouse heart.</a> Science. 331, 1078-1080 (2011).</li><li>Mahmoud, A. 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M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+hypothermia+for+general+anesthesia+in+preweanling+rodents.">Use of hypothermia for general anesthesia in preweanling rodents.</a> Physiol Behav. 38, 887-890 (1986).</li><li>Laflamme, M. A., Murry, C. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regenerating+the+heart.">Regenerating the heart.</a> Nat Biotechnol. 23, 845-856 (2005).</li><li>Laflamme, M. A., Murry, C. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Heart+regeneration.">Heart regeneration.</a> Nature. , 326-335 (2011).</li><li>Jesty, S. 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本文的出版费用由精细的科学工具的礼物，侯健博士进行了赞助。

Cardiac regeneration shows potential for the treatment and prevention of heart failure1, 2. Animal models are indispensable and play a critical role in understanding how cardiac regeneration occurs3-6. Many amphibians and fish regenerate heart tissue in response to injury, providing insight into our understanding of human cardiovascular disease13, 14. In terms of evolution, however, the pathophysiology should be more conserved between a mouse model and humans. Heart regeneration in mammalian animal models is a relatively new but burgeoning research field for the therapeutics of heart failure3-6. 
Recently, two surgical approaches, apical resection and myocardial infarction, have been established in the study of heart regeneration in neonatal mice6. Although apical resection provides a relatively easy and direct model for loss and/or injury of cardiomyocytes, the main limitation of apical resection compared to myocardial infarction is that this surgical method cannot be performed beyond P7 due to high mortality6. There are, however, a number of ways to reduce mortality with this method. For apical surgery on P7 pups, the pups are cooled to 16&#176;C for optimum hypothermia anesthesia. Generally, sterile conditions and surgical proficiency are critical for successful apical resection surgery. To improve survival, the surgery should be performed as quickly and gently as possible and a minimally invasive operation will reduce bleeding. Additionally, ICR/CD-1 mice are thought as good foster mothers and can effectively avoid of severe maternal cannibalization. For example, placing the P0 C57BL/6 pups with an ICR/CD-1 mother increases the survival rates of P1 pups with apical resection approximately from 60% to 80%ref.6. In addition, cryoinjury is an alternative procedure for study of cardiac regeneration. Compared to apical resection, cryoinjury model represents a different regenerative response and may be a more reproducible model15, 16. Thus far, a comparison of apical resection with other models warrants further investigations. 
Using phospho-histone H3 and 5-bromo-2-deoxyuridine staining, Porrello and colleagues showed that cardiomyocyte proliferation contributes to the heart regeneration of neonatal P1 mice after apical resection response. Moreover, no significant cardiac hypertrophy and increase of cell size have been observed in mice with apical resection relative to sham-operated controls. After apical resection of 7-day-old mice, there is no regenerative response for myocardium5. A more detailed time course analysis of morphology and cardiac fibrosis after apical resection has been demonstrated5. Of note, the usefulness of apical resection in neonatal mouse models for heart regeneration research has been questioned by Anderson and colleagues8. Although many independent groups have demonstrated the reproducibility of apical resection, variations in the details of surgical procedures and different amounts of resected myocardium might be responsible for confusing results10. Quantification of the genomic DNA in resected heart is helpful for control of minimal chamber exposition and reproducibility of this technique. Additional research will be needed to fully understand neomyogenesis and complete vs. incomplete heart regeneration in the apical resection model8-11.
The main aim of this study is to present the procedures of apical resection in a visualized way. This video of apical resection in the neonatal mouse will be helpful to increase the use of this method and teach it to heart regeneration researchers. In addition, it may promote the pursuit of better approaches for mammalian heart regeneration in animal models and facilitate the discovery and translation of the molecular and cellular mechanisms responsible for heart regeneration in humans.

Prolonged human life span leads to various aging- and lifestyle-related diseases, including heart failure, a leading cause of mortality. However, without replacement of lost or dysfunctional cardiac muscle cells, current therapeutics can only transiently improve cardiac function1, 2. Thus, it is necessary to discover and develop innovative strategies for cardiac regeneration and repair. The adult mammalian heart has limited regenerative potential. Studies from lower vertebrates, such as urodele amphibians and teleost fish, have provided unprecedented insights into the molecular and cellular mechanisms underlying heart regeneration3, 4. Recently, a neonatal mouse model of heart regeneration has emerged that might enable identification and characterization of more evolutionarily conserved pathophysiological events required for human heart regeneration5. 
Apical resection refers to the surgical removal of left ventricular apex. This procedure is restricted to 1- to 7-day-old (P1 to P7) mice due to its high lethality in older mice6. The cardiac regeneration process in neonatal mice after apical resection is expected to be as follows: (I) rapid and effective formation of a hematoma to seal the apex and prevent exsanguination; (II) cardiomyocyte regeneration and restoration of systolic function5, 7. Recent work has stimulated debate on the significance and efficiency of this model8-11. Thus, it is important to present the apical resection clearly and in detail. To this end, this protocol vividly and specifically describes a video of how I did apical resection based on a previous protocol6. 
Understanding the molecular mechanisms underlying cardiac regeneration is of importance for treatment of heart disease characterized by loss and/or injured cardiomyocytes, such as heart failure1, 2. Given the current and promising progress of apical resection in the research of cardiac regeneration, this study could promote the use of this technique and its uses in cardiac regeneration research.

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</table>

apical resection mouse model to study early mammalian heart regeneration

心脑血管疾病困扰着整个世界，由于密集的生活方式的改变。心脏再生持有修复和恢复因受伤和疾病失去了心肌巨大潜力。相反，某些低等脊椎动物的强劲心脏再生，成年哺乳动物心脏通常显示为心脏的再生和修复能力最低。然而，最近的研究已经引起了相当大的科学兴趣地注意到，产后天之间1〜7（P1到P7），新生小鼠心脏保留显著再生潜能根尖切除术（ 即 ，手术截肢和左心室心尖曝光）后的发现。超过这一发现一个主要的争论可能是由于不同的手术相关的程序中的努力来复制或扩大在此重要的发现使用。这些指令动态地呈现材料和方法根尖切除的小鼠模型。其显着的步骤该啮齿动物surviva的升手术涉及低温麻醉，开胸，心脏心室心尖手术截肢，缝合和老鼠的恢复。描述可以扩大根尖切除的小鼠模型的心血管研究的应用程序的方法。

乳鼠被安乐死1，2，和21天后根尖切除术，并收集了H＆E和马尾松的三色染色他们的心。蓝色在马松三色染色表示心外膜细胞外基质5的沉积。与成功的根尖切除，血块被有效地形成，以密封的LV之一天后根尖切除， 如图1A。血凝块和早期心脏纤维化的逐渐再吸收观察，并代之以心肌组织发生直到心肌完全再生发生21天根尖切除后（图1B 和C）。形态学分析表明21天手术后（图1C 和D）切除和假手术的心之间没有差别。 <img alt="图1" src="/files/ftp_upload/53488/53488fig1.jpg" /> 图1.代表H＆E和马尾松的三色染色，新生小鼠心脏1（A），2（B），或根尖切除术后21（C）天，假手术（D）后21天心肌。对于每个子图中，左侧面板的比例尺为1毫米，右面板的比例尺为100微米。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/53488/53488fig1large.jpg" target="_blank">请点击此处查看该图的放大版本。</a>

Watch this Scientific Journal Video about Apical Resection Mouse Model to Study Early Mammalian Heart Regeneration at JoVE.com

Apical Resection Mouse Model to Study Early Mammalian Heart Regeneration

A step-by-step video protocol of apical resection is demonstrated in this study. Apical resection is a recently highlighted surgical approach in mammalian heart regeneration research. This study may promote the application of apical resection as a standard methodology in research into the mechanism underlying heart regeneration.

根尖切除小鼠模型来研究早期哺乳动物心脏再生

Cardiovascular disease plagues the whole world due to intensive lifestyle changes. Heart regeneration holds great promise for repairing and restoring ...

apical-resection-mouse-model-to-study-early-mammalian-heart

Nanyang Technological University

Research

JoVE Journal

Medicine

11.2K 次观看.  National Institutes of Health. A step-by-step video protocol of apical resection is demonstrated in this study. Apical resection is a recently highlighted surgical approach in mammalian heart regeneration research. This study may promote the application of apical resection as a standard methodology in research into the mechanism underlying heart regeneration.

视频: Apical Resection Mouse Model to Study Early Mammalian Heart Regeneration

Orthotopic Aortic Transplantation: A Rat Model to Study the Development of Chronic Vasculopathy

Research models of chronic rejection are essential to investigate pathobiological and pathophysiological processes during the development of transplant vasculopathy (TVP).
The commonly used animal model for cardiovascular chronic rejection studies is the heterotopic heart transplant model performed in laboratory rodents. This model is used widely in experiments since Ono and Lindsey (3) published their technique. To analyze the findings in the blood vessels, the heart has to be sectioned and all vessels have to be measured.
Another method to investigate chronic rejection in cardiovascular questionings is the aortic transplant model (1, 2). In the orthotopic aortic transplant model, the aorta can easily be histologically evaluated (2). The PVG-to-ACI model is especially useful for CAV studies, since acute vascular rejection is not a major confounding factor and Cyclosporin A (CsA) treatment does not prevent the development of CAV, similar to what we find in the clinical setting (4). A7-day period of CsA is required in this model to prevent acute rejection and to achieve long-term survival with the development of TVP.
This model can also be used to investigate acute cellular rejection and media necrosis in xenogeneic models (5).

This video demonstrates the orthotopic aortic transplant model as a simple model to study the development of transplant vasculopathy (TVP) in rats.

主动脉原位移植大鼠模型，研究慢性血管病变的发展

Research models of chronic rejection are essential to investigate pathobiological and pathophysiological processes during the development of transplant ...

科研

医学

A Mouse Model of in Utero Transplantation

The transplantation of stem cells and viruses in utero has tremendous potential for treating congenital disorders in the human fetus. For example, in utero transplantation (IUT) of hematopoietic stem cells has been used to successfully treat patients with severe combined immunodeficiency.1,2 In several other conditions, however, IUT has been attempted without success.3 Given these mixed results, the availability of an efficient non-human model to study the biological sequelae of stem cell transplantation and gene therapy is critical to advance this field. We and others have used the mouse model of IUT to study factors affecting successful engraftment of in utero transplanted hematopoietic stem cells in both wild-type mice4-7 and those with genetic diseases.8,9 The fetal environment also offers considerable advantages for the success of in utero gene therapy. For example, the delivery of adenoviral10, adeno-associated viral10, retroviral11, and lentiviral vectors12,13 into the fetus has resulted in the transduction of multiple organs distant from the site of injection with long-term gene expression. in utero gene therapy may therefore be considered as a possible treatment strategy for single gene disorders such as muscular dystrophy or cystic fibrosis. Another potential advantage of IUT is the ability to induce immune tolerance to a specific antigen. As seen in mice with hemophilia, the introduction of Factor IX early in development results in tolerance to this protein.14 
In addition to its use in investigating potential human therapies, the mouse model of IUT can be a powerful tool to study basic questions in developmental and stem cell biology. For example, one can deliver various small molecules to induce or inhibit specific gene expression at defined gestational stages and manipulate developmental pathways. The impact of these alterations can be assessed at various timepoints after the initial transplantation. Furthermore, one can transplant pluripotent or lineage specific progenitor cells into the fetal environment to study stem cell differentiation in a non-irradiated and unperturbed host environment.
The mouse model of IUT has already provided numerous insights within the fields of immunology, and developmental and stem cell biology. In this video-based protocol, we describe a step-by-step approach to performing IUT in mouse fetuses and outline the critical steps and potential pitfalls of this technique.

A Mouse Model of in Utero Transplantation

The mouse model of in utero transplantation is a versatile tool that can be used to study the potential clinical applications of stem cell transplantation and gene therapy in the fetus. In this protocol, we present a general approach to performing this technique

一个小鼠模型在子宫内移植

The transplantation of stem cells and viruses in utero has tremendous potential for treating congenital disorders in the human fetus.  For example, in ...

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.

肾缺血再灌注损伤:损伤的小鼠模型和再生

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

Ferric Chloride-induced Thrombosis Mouse Model on Carotid Artery and Mesentery Vessel

Severe thrombosis and its ischemic consequences such as myocardial infarction, pulmonary embolism and stroke are major worldwide health issues. The ferric chloride injury is now a well-established technique to rapidly and accurately induce the formation of thrombi in exposed veins or artery of small and large diameter. This model has played a key role in the study of the pathophysiology of thrombosis, in the discovery and validation of novel antithrombotic drugs and in the understanding of the mechanism of action of these new agents. Here, the implementation of this technique on a mesenteric vessel and carotid artery in mice is presented. The method describes how to label circulating leukocytes and platelets with a fluorescent dye and to observe, by intravital microscopy on the exposed mesentery, their accumulation at the injured vessel wall which leads to the formation of a thrombus. On the carotid artery, the occlusion caused by the clot formation is measured by monitoring the blood flow with a Doppler probe.

The FeCl3 induced thrombosis model in mice is described herein. A method to monitor thrombus growth by intravital microscopy observation on a mesenteric vessel and by blood flow measurement in the carotid artery is presented.

三氯化铁诱发血栓形成小鼠模型上的颈动脉和肠系膜血管

Severe thrombosis and its ischemic consequences such as myocardial infarction, pulmonary embolism and stroke are major worldwide health issues. The ferric ...

Vein Interposition Model: A Suitable Model to Study Bypass Graft Patency

Bypass grafting is an established treatment method for coronary artery disease. Graft patency continues to be the Achilles heel of saphenous vein grafts. Research models for bypass graft failure are essential for a better understanding of pathobiological and pathophysiological processes during graft patency loss. Large animal models, such as pigs or sheep, resemble human anatomical structures but require special facilities and equipment. This video describes a rat vein interposition model to investigate vein graft patency loss. Rats are inexpensive and easy to handle. Compared to mouse models, the convenient size of rats permits better operability and enables a sufficient amount of material to be obtained for further diverse analysis. In brief, the inferior epigastric vein of a donor rat is harvested and used to replace a segment of the femoral artery. Anastomosis is conducted via single stitches and sealed with fibrin glue. Graft patency can be monitored non-invasively using duplex sonography. Myointimal hyperplasia, which is the main cause for graft patency loss, develops progressively over time and can be calculated from histological cross sections.

This video demonstrates a model to study the development of myointimal hyperplasia after venous interposition surgery in rats.

静脉介入型号:研究旁路移植通畅一个合适的模型

Bypass grafting is an established treatment method for coronary artery disease. Graft patency continues to be the Achilles heel of saphenous vein grafts. ...

A Mouse Model of Orthopedic Surgery to Study Postoperative Cognitive Dysfunction and Tissue Regeneration

Surgery is commonly used to improve and maintain quality of life. Unfortunately, in vulnerable patients such as the elderly, complications may occur and significantly diminish the outcome. Indeed, after routine orthopedic surgery to repair a fracture, as many as 50% of elderly patients suffer from neurologic complications like delirium. Also, the capacity to heal and regenerate tissue after surgery decreases with age, and can impact the quality of fracture repair and even osseous integration of implants. Thus, a better understanding of mechanisms that drive these age-dependent changes could provide strategic targets to minimize risk for such complications and optimize outcomes. Here, we introduce a clinically relevant mouse model of tibial fracture. The postoperative changes in these mice mimic some of the cognitive impairments commonly observed after routine orthopedic surgery in humans. Briefly, an incision is performed in the right hind limb under strictly aseptic conditions. Muscles are disassociated, and a 0.38-mm stainless steel pin is inserted into the upper crest of the tibia, inside the intramedullary canal. Osteotomy is then performed, and the wound is stapled. We have used this model to investigate the effects of surgical trauma on postoperative neuroinflammation and behavioral changes. By applying this fracture model in combination with parabiosis, a surgical model in which 2 mice are anastomosed, we have studied cells and secreted factors that systemically rejuvenate organ function and tissue regeneration after injury. By following our step-by-step protocol, these models can be reproduced with high fidelity, and can be adapted to interrogate many biologic pathways that are altered by surgical trauma.

This protocol describes a mouse model of orthopedic surgery that has been used to study mechanisms of postoperative neuroinflammation and behavioral changes, and when combined with parabiosis, to study tissue regeneration during aging.

骨科手术的小鼠模型研究术后认知功能障碍与组织再生

Surgery is commonly used to improve and maintain quality of life. Unfortunately, in vulnerable patients such as the elderly, complications may occur and ...

Isometric Contractility Measurement of the Mouse Mesenteric Artery Using Wire Myography

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and drugs. It is widely used in many studies on the physiological functions of vascular smooth muscle, the pathogenesis of vascular diseases such as hypertension, and the development of smooth muscle relaxant drugs. The mouse is a widely used model animal with a large pool of disease models and genetically modified strains. We introduced this method to measure the isometric contraction of mouse mesenteric artery in detail. A 1.4-mm segment of mouse mesenteric resistance artery was isolated and mounted on a myograph chamber by passing two steel wires through its lumen. After equilibration and normalization steps, the vessel segment was potentiated by a high-K+ solution twice prior to the contraction assay. As an example of the application of this method in drug development, we measured the relaxant effect of a novel natural substance, neoliensinine, isolated from a Chinese herb, embryos of the lotus seed (Nelumbo nucifera Gaertn.) on mouse mesenteric arteries. The vessel segments mounted on the myograph chamber were stimulated with a high-K+ solution. When the force tension reached a stable sustained phase, cumulative doses of neoliensinine were added to the chamber. We found that neoliensinine had a dose-dependent relaxant effect on smooth muscle contraction, thus suggesting that it bears potential activity against hypertension. In addition, as the vessel segment can survive at least 4 hours after mounting and maintain contractility induced by the high-K+ solution for many times, we suggest that the wire myograph system may be used for the time-consuming process of drug screening.

The wire myograph technique is used to investigate vascular smooth muscle functions and screen new drugs. We report a detailed protocol for measuring the isometric contractility of the mouse mesenteric artery and for screening new relaxants of vascular smooth muscle.

用线 Myography 测定小鼠肠系膜动脉的等轴收缩力

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and ...

A Cryoinjury Model to Study Myocardial Infarction in the Mouse

The use of animal models is essential for developing new therapeutic strategies for acute coronary syndrome and its complications. In this article, we demonstrate a murine cryoinjury infarct model that generates precise infarct sizes with high reproducibility and replicability. In brief, after intubation and sternotomy of the animal, the heart is lifted from the thorax. The probe of a handheld liquid nitrogen delivery system is applied onto the myocardial wall to induce cryoinjury. Impaired ventricular function and electrical conduction can be monitored with echocardiography or optical mapping. Transmural myocardial remodeling of the infarcted area is characterized by collagen deposition and loss of cardiomyocytes. Compared to other models (e.g., LAD-ligation), this model utilizes a handheld liquid nitrogen delivery system to generate more uniform infarct sizes.

This article demonstrates a model to study cardiac remodeling after myocardial cryoinjury in mice.

研究小鼠心肌梗死的低温损伤模型

The use of animal models is essential for developing new therapeutic strategies for acute coronary syndrome and its complications. In this article, we ...

Blood Circuit Reconstruction in an Abdominal Mouse Heart Transplantation Model

The surgical technique of heterotopic abdominal heart transplantation in mice is a standard model for research in transplantation immunology. Here, the established technique for a modified blood circuit reconstruction in a heterotopic abdominal heart transplantation model is presented. This method uses the intrathoracic inferior vena cava (IIVC) instead of the pulmonary artery of the donor heart for the anastomosis to the inferior vena cava of the recipient. It is facilitating and improving success rates for abdominal heart transplantation in mice.

A novel technique for blood circuit reconstruction in a heterotopic abdominal mouse heart transplantation model is demonstrated.

腹部小鼠心脏移植模型中的血液回路重建

The surgical technique of heterotopic abdominal heart transplantation in mice is a standard model for research in transplantation immunology. Here, the ...

An In Vivo Mouse Model of Total Intravenous Anesthesia During Cancer Resection Surgery

Anesthesia is a routine component of cancer care that is used for diagnostic and therapeutic procedures. The anesthetic technique has recently been implicated in impacting long-term cancer outcomes, possibly through modulation of adrenergic-inflammatory responses that impact cancer cell behavior and immune cell function. Emerging evidence suggests that propofol-based total intravenous anesthesia (TIVA) may be beneficial for long-term cancer outcomes when compared to inhaled volatile anesthesia. However, the available clinical findings are inconsistent. Preclinical studies that identify the underlying mechanisms involved are critically needed to guide the design of clinical studies that will expedite insight. Most preclinical models of anesthesia have been extrapolated from the use of anesthesia in in vivo research and are not optimally designed to study the impact of anesthesia itself as the primary endpoint. This paper describes a method for delivering propofol-TIVA anesthesia in a mouse model of breast cancer resection that replicates key aspects of clinical delivery in cancer patients. The model can be used to study mechanisms of action of anesthesia on cancer outcomes in diverse cancer types and can be extrapolated to other non-cancer areas of preclinical anesthesia research.

An In Vivo Mouse Model of Total Intravenous Anesthesia During Cancer Resection Surgery

This paper describes a method for modeling total intravenous anesthesia (TIVA) during cancer resection surgery in mice. The goal is to replicate key features of anesthesia delivery to patients with cancer. The method allows investigation of how anesthetic technique affects cancer recurrence after resection surgery.

癌症切除手术中全静脉麻醉的 体内 小鼠模型

Anesthesia is a routine component of cancer care that is used for diagnostic and therapeutic procedures. The anesthetic technique has recently been ...