鼠左前降支（LAD）冠状动脉结扎：改进和简化模型的心肌梗死
Summary
We provide a reliable method for left anterior descending artery (LAD) ligation in a mouse model. This method is comparatively less invasive than other methods, involving endotracheal intubation, a left-sided thoracotomy approach, and thoracentesis. This method can be used as a model for both acute and chronic myocardial infarction (MI).
Abstract
缺血性心脏疾病（IHD），或急性冠脉综合征（ACS），是死亡的在美国的主要原因之一。 IHD的特征在于血液供应减少到心脏，导致氧气的损失和心脏肌肉的随后的坏死。该MI模型已经得到普及其作为短期缺血再灌注模型和一个长期的永久的结扎模型使用。下面，我们描述了LAD的结扎的可靠方法。随着鼠标基因工程技术变得越来越先进，并与质量鼠手术器械的日益普及，鼠标已经成为MI手术的热门机型。我们的手术模型包括使用对鼠标的快速恢复的易可逆麻醉剂;微创气管内插管，而不涉及气管切开术;并通过原开胸部位的胸腔而不在胸部额外的切口，如在一些其他方法来完成，从胸腔至有效地去除过量的血液和空气。此方法相对比其它方法，这极大地减少了外科手术和外科手术后的并发症和死亡率及改善再现性侵入性更小。
Introduction
冠状动脉疾病，或ACS，是最常见的心血管事件，将被认为是发病率和死亡率世界各地的主要原因在2020年1。 ACS的原因是心肌血栓的存在由于冠状动脉粥样硬化斑块，阻止或减少血液流向心脏组织2的破裂。因此，有临床症状的急性心肌缺血的存在一致，如心肌梗死（MI）3,4。 MI导致心肌细胞的质量损失和进展为病理性心室重构，从而导致心功能不全和心脏衰竭5,6。
其中一个最有效的方法来研究IHD一直模仿人类心肌梗死的动物模型。这是由闭塞的LAD实现老鼠。使用这个模型，我们研究如何心脏可以从IHD造成的损害进行保护。
在过去的十年中，研究人员使用较大的动物模型，以较小的动物，包括大鼠小鼠移位移动。较小的小鼠模型开始被优选的原因很多，其中包括它们的小尺寸，大产仔数，维护成本低，和短的怀孕期，以及用于转基因和基因敲除模型7的膨胀可用性。虽然小鼠体积小，专为他们设计的新的手术器械已经在这方面的发展援助。我们的方法利用这些新的手术器械。
虽然一些方法来实现的侵入气管切开术，我们使用气管插管的微创方法。使用口咽开销照明，我们插管不会造成任何切口，提供T A更安全，创伤小经验他的动物。然后将鼠标放置在呼吸机和在整个过程中保持在异氟醚。由于药物产生的麻醉时间短，只需要几分钟，让动物从麻醉一旦停产恢复。我们的手术模型还包括微创胸腔穿刺。从胸腔胸腔穿刺术使用仔细取出血液和过量空气通过原开胸切口已经解决了LAD结扎的共同术后并发症：张力气胸。该方法中，这消除了在其它方法中，一个用于气管切开术，另一个用于胸腔-已经产生了更少的外科手术后的并发症中使用的两个附加的切口的需要，并大幅度降低了死亡率。
Protocol
Representative Results
Discussion
随着越来越多地使用在实验室MI模型，所描述的过程旨在提高小鼠的效率和生存率，同时尽量减少他们的手术后疼痛和不适。该协议努力通过使许多改进到LAD结扎过程的各个方面，以尽量减少死亡率。有一些区别。利用氯胺酮和赛拉嗪与异氟醚诱导以来，由于麻醉的持续时间较长的利益有些小鼠气管插管的研究，表明死亡率增加8。我们的方法只使用异氟烷诱导，大?…
Declarações
The authors have nothing to disclose.
Acknowledgements
This model was developed with the support of the National Institute of General Medical Sciences (NIGMS)/the National Institute of Health (NIH) grant 1P20GM103652 (Project# 3) (to MRA) and the American Heart Association (AHA) Grant-in-Aid 14GRNT20460291 (to MRA); the Brazilian government grant CAPES (to KR and FR); and a Brown University LINK award (to IM). We also acknowledge the outstanding technical support from our veterinarians and animal facility staff.
Materials
| High-Intensity Light Source | Harvard Apparatus | 72-0215 | |
| SurgiSuite Operating Platform | Kent Scientific Corporation | SurgiSuite | Uses a rechargeable, battery-operated far infrared warming pad. Charge overnight before surgery. |
| SurgiSuite LED Lighting Kit | Kent Scientific Corporation | SURGI-5003 | |
| Hot Bead Sterilizer | Fine Science Tools | 18000-45 | Preheating takes 15-20 minutes. Instruments take 20 seconds to sterilize. |
| Small Rodent Anesthesia System | VetEquip Inc. | 901810 | |
| Isofluorane | Piramal Enterprises | 66794-017-10 | |
| Buprenorphine | Rhode Island Hospital Pharmacy | NDC 12496-0757-1, 12496-0757-5 | |
| Surgical Loupes | Roboz | RS-6687 | |
| Small Rodent Ventilator | Harvard Apparatus | 73-0043 | |
| Lubricating Drops | Thermo Fisher Scientific | 19-898-350 | |
| Electric Razor | Kent Scientific Corporation | CL 9990-1201 | |
| Hair Removal Cream | Nair | ||
| Medical Tape | Thermo Fisher Scientific | 18-999-380 | |
| Betadine | Thermo Fisher Scientific | 19-027136 | |
| 70% Isopropanol Wipes | Thermo Fisher Scientific | 22-363-750 | |
| Surgical Drapes | Braintree | SP-TS | |
| Surgical Gloves | Thermo Fisher Scientific | 18999102D | |
| 5-0 Polypropylene Sutures | Ethicon | 8630G | |
| 8-0 Nylon Sutures | Fine Science Tools | 12051-08 | |
| Platinum-Cured Tubing | Harvard Apparatus | 72-1042 | 0.3 mm inside diameter x 0.6 mm outside diameter |
| 0.9% Saline | Thermo Fisher Scientific | 19-310-207 | |
| 4-0 Polypropylene Sutures | Ethicon | 8631G | |
| 1 CC Syringe with 25-Gauge Needle | Thermo Fisher Scientific | 14-826-100 | |
| Scissors | Kent Scientific Corporation | INSS600225 | |
| Forceps | Kent Scientific Corporation | INS700100 | |
| Cotton Swabs | Thermo Fisher Scientific | 23-400-118 | |
| IV Catheter, 20-Gauge | Thermo Fisher Scientific | NC9892181 | |
| Retractor | Kent Scientific Corporation | INS 750369 | |
| Forceps | Fine Science Tools | 11003-12 | |
| Dissecting Forceps, Straight | Kent Scientific Corporation | INS 700101 | |
| Dissecting Forceps, Curved | Kent Scientific Corporation | INS 700103 | |
| Hemostatic Forceps, Straight | Kent Scientific Corporation | INS 750451 | |
| Hemostatic Forceps, Curved | Kent Scientific Corporation | INS 750452 | |
| Tissue Forceps | Kent Scientific Corporation | INS 700131 | |
| Needle Holder | Kent Scientific Corporation | INS 600109 | |
| Scissors | Kent Scientific Corporation | INS 600225 |
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