植入异丙酮醇微型泵，以诱导小鼠心力衰竭
Summary
通过植入的渗透泵长期给用异丙酮醇，已被广泛用于模拟小鼠的晚期心力衰竭。在这里，我们描述了手术微型泵植入在持续异丙酮醇给3周内的详细方法，以及成功创建模型的超声心动图评估。
Abstract
Isoproterenol（ISO）是一种非选择性β-肾上腺素激动剂，广泛用于诱导小鼠心脏损伤。虽然急性模型模仿压力引起的心肌病，而通过渗透泵施用的慢性模型模仿人类晚期心力衰竭。所述协议的目的是使用植入的微型泵在小鼠中创建慢性ISO引起的心力衰竭模型。该协议已用于诱导100+系近亲繁殖小鼠的心力衰竭。手术泵植入技术被详细描述，可能与任何有兴趣在小鼠中创建心力衰竭模型的人相关。此外，还介绍了基于每个菌株的超声心动图参数和模型开发的预期时间，每周心脏重塑变化。总之，该方法简单易用。通过植入式微型泵在3至4周内连续施用ISO，足以诱导心脏重塑。最后，通过连续超声心动图显示肥大、心室扩张和功能障碍，可以评估ISO模型创建的成功。
Introduction
心力衰竭与减少弹出分数（HFrEF）伴随着一个公认的补偿反应的同情神经系统，以保持心血管平衡1。慢性活化观察到血液动力学压力和对心脏和循环的有害影响。这些已成为当代心力衰竭药物治疗的基石，是心力衰竭和神经激素系统治疗对抗发展的重要机制1。
有几个小鼠模型可用于心脏衰竭的基本调查。基因模型对探索分子疗法和研究信号通路很有吸引力。然而，这些模型可能与常见的心力衰竭形式无关。其他常见模型包括左前下降 （LAD） 动脉结扎、 横端收缩 （TAC） 和异丙酮醇 （ISO），每个模型针对不同的病理病因2、3、4、5 ，6.LAD动脉结扎诱导前壁心肌梗死，从而创建缺血性心肌病的专用模型。TAC诱导急性压力过载，形成心力衰竭的高血压模型。虽然可以测量压力梯度，允许肥大的分层，但高血压的急性发病缺乏直接的临床相关性4。LAD 和 TAC 型号都需要高水平的外科专业知识才能执行。急性ISO心力衰竭模型模仿应激引起的心肌病，也称为Takotsubo病，其特征是卡他索明的明显增加和左心室的活性，模仿急性心肌梗死7， 8.相比之下，慢性ISO型心力衰竭模型存在晚期心力衰竭的症状特征，慢性高浓度的儿茶酚胺1。慢性 ISO 模型的优点是，它提供模仿晚期心力衰竭的慢性肾上腺素刺激，并且相对容易产生。研究者应该选择一个模型，最好地概括他们感兴趣的病理学。
这种方法的总体目标是诱导小鼠的心力衰竭，使用植入的微型泵，释放 ISO 持续模仿慢感活化发现心力衰竭患者 1 。该方法简单易用。虽然小鼠菌株之间有明显差异，但以30毫克/千克/天在30mg/kg/天下施用3至4周的ISO足以诱导大多数小鼠进行心脏重塑。具体来说，ISO在第1周导致亲肥大补偿阶段，随后在第2周和第32周出现壁变薄、心室扩张和收缩功能下降。ISO模型创建的成功可以通过连续的超声心动图在体内评估，证明肥大、扩张和心室功能障碍，以及通过组织学和分子评估采集的心脏组织进行肌萎缩性功能评估。脂质积累，纤维化，ER压力，凋亡，和基因表达9，10，11，12。
Protocol
Representative Results
Discussion
我们已经将这种方法应用于超过100多种近亲小鼠，以评估慢性β-肾上腺素刺激引起的心脏结果2，13。已知在小鼠菌株中存在异丙酮醇的易感性显著差异，可根据所需兴趣菌株进行定制16。这可能是由于小鼠菌株17之间β-肾上腺素受体功能的变化，自主神经系统活性16的菌株依赖性差异，β-肾上腺素受?…
Disclosures
The authors have nothing to disclose.
Acknowledgements
作者承认NIH K08 HL133491的资金支持。
Materials
| Micro-Osmotic Pump System with Flow Moderator in Place | Alzet | Model 1004 | Includes filling tube, flow moderator and pump body |
| (-)-Isoproterenol hydrochloride | Sigma-Aldrich | 16504-1G | (-)-Isoproterenol hydrochloride is a powder that needs to be stored at -20°C. |
| 1 ml sterile syringe | VWR | BD309602 | |
| 30 W LED Fiber optic O-ring light microscope illuminator | AmScope | SKU: LED-30WR | |
| 5-0 COATED VICRYL (polyglactin 910) Suture | Ethicon | J303H | 5-0, absorbable |
| Fine Scissors – Sharp | FST | 14060-09 | |
| Glass beads | FST | 18000-46 | |
| Hot bead sterilizers | FST | 18000-50 | |
| Iris forceps | WPI | 15915 | |
| Look Sharpoint 6-0, 18" Black Nylon Monofilament Suture | LOOK | AA-2176 | 6-0, non-absorbable |
| Needle holder | WPI | 15926 | |
| Normal Saline, 0.9% NaCl | Fisher | 89167-772 |
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