笔者想从NHLBI（K08 HL102066和R01 HL114832）承认资金。

执行任何在本协议中所描述的过程之前，获得由当地机构动物护理和使用委员会的批准。 1.安装试验装置 注意:在麻醉动物进行该程序和数据的质量成比例提供给动物的麻醉剂支持体的质量。该第一部分将详细介绍必要的设备和程序，以提供麻醉的小鼠的同时执行该协议。 <ol><li>选择麻醉协议。吸入麻醉剂有用于执行光伏回路分析许多有益的性能，但也有一些可注射的协议已被使用为好。查看选择的麻醉剂政权以获取更多信息的讨论。 </li><li>固定压缩氧气罐到手术台或壁手术部位附近。 </li><li>如果使用吸入麻醉剂，用蒸发器，以保证适当的剂量。每年校准汽化器，以确保他们所提供麻醉气体的适当剂量。连接蒸发器到一个流量计，它允许在该气体进入麻醉剂回路中的速率的控制。设定在0.5 - 1.0升/分。 </li><li>使用的歧管，以允许麻醉气体的，以1定向流量）的吸气室，2）的掩模，以及3）的呼吸机。清除麻醉气体是非常重要的，并应在一个活动的系统来执行，要么通风口进入通风橱（或其它类似建筑物基础设施），或通过旨在除去麻醉气体的罐。 注:与当地的职业卫生官员检查，以确保符合当地的法规。 </li><li>通过使用加热垫和/或加热灯保持体温。持续监测体温用直肠体温计。这将允许对主动增加或加热减小，以确保一个生理体温（ͭ6;血液动力数据的采集期间37℃）。 </li><li>流体提供支持，以抵消失血昏迷体积损失。 <ol><li>抽出1 ml等于25％白蛋白和在注射器加入1.5毫升的0.9％NaCl的制备白蛋白的10％溶液中的0.9％NaCl。 </li><li>准备低残留量血管内导管。 <ol><li>用钳子把美眉0.5英寸30号针头的塑料轮毂。用持针器，把握针并取出枢纽。刮使用止血钳针头剩余的粘合剂。插入针的钝端插入微孔管的长度。使用长度小于20英寸的管道。 </li></ol></li><li>使用注射泵，允许精确卷交付。 </li></ol></li><li>确保高品质的光伏数据的收集适当的通风。有多种可供购买鼠标的呼吸机。压力控制呼吸机提供吸入剂所需要的封闭环境nesthetic气体和提供在手术过程中的通风的更好的控制。 <ol><li>确保吸气压力限制为&lt;15 cm H2O的，以防止气压伤。设置通气机呼吸周期的35％时，提供吸气脉冲。在4的一级使用呼气末正压（PEEP） - 5 cm H2O的将大大提高鼠标的通风，防止肺不张及配套的气体交换。 </li><li>限制死腔远端的通气电路中的Y型接头。这是至关重要的，因为鼠标的潮气量是非常小的和新鲜的空气灵感交付任何死角减去。 </li><li>通过削减尖端关20号留置血管内导管的创建一个鼠标大小的气管（ET）管。这提供了更容易地插入一锥形点。放置的切断端插入麻醉剂电路的Y接头。 </li><li>使用软管在呼吸电路。在管道的任何结构的内存将创建具有拉气管插管出鼠标的气道的潜在的外部力量。 </li><li>让鼠标确定通过使用抑制内源性呼吸动力的最低利率的呼吸速率。开始以每分钟约60次呼吸的相对缓慢的呼吸速率。 注意:使用适当的通风鼠标应该很少的努力呼吸。然而，如果通风不足，CO 2的血液中的积聚将启动由鼠标呼吸努力。如果发生此种情况，增加呼吸频率是增加肺泡通气一个直接的方式。通常有必要增加响应于海拔与β-肾上腺素能受体刺激相关的心脏的工作负荷的呼吸速率。 </li><li>一旦呼吸电路制备，压力由堵塞气管的前端（ET）的管测试系统用手指。确保≈10CMH 2 O的气道压力这个试验前应在每个步骤进行。 </li></ol></li></ol> 2.手术方法<ol><li>使用小镊子和剪刀等设备从表1中 。所有仪表是相当小的，以允许在放大手术区域容易使用。使用外科立体显微镜，为外科手术过程的若干方面提供足够的放大。 </li><li>使用烧灼的手术过程中最大限度地止血。 注:有几个大类烧灼的。 Thermocautery加热将通过肌肉组织切割和止血薄金属元素。这些系统最初相对便宜;然而需要注意的是，导线的提示是脆弱和相对昂贵的是重要的。电灼系统更昂贵的最初购买，但提示是很坚固的，并且不会需要被更换ð。 </li><li> 诱导和手术准备 <ol><li>获得体重鼠标。 </li><li>鼠标放置成填充有5％异氟醚的感应腔室。 注意:鼠标不能比在此环境中的活几分钟。只有45 - 60秒都需要鼠标失去翻正反射（努力当放置在其背面或侧面翻转）。 </li><li>一旦翻正反射丧失，异氟烷浓度降低至2％，并打开麻醉气体到面罩。 </li><li>很快鼠标转移到手术台，并与面罩内的鼻子将其放置在背卧。 </li><li>如果使用电，用生理盐水浸湿纱布电连接鼠标电灼系统的接地垫。 </li><li>安全与手术磁带四肢。此胶带提供即使当湿粘合性能。 </li><li>将监测芯体直肠测温器温度。用胶带固定。 </li><li>应用脱毛鼠标的颈部和胸部。等待2 - 3分钟为脱毛工作，然后再从用棉签这些区域和/或实验室擦拭除去皮毛。 注意:不要求手术野的悬垂，因为这是一个非生存的方法，但可能希望限制外科医生暴露于烧灼接地垫，如果使用的话。 </li><li>一旦鼠标准备向手术，通过执行脚趾捏评估小鼠的外科平面。一旦保证适当的麻醉深度的小鼠是准备用于第一切口。 </li></ol></li><li>获得通过口头插管或气管切开气道的控制权。气管切开术是一种方便的方法是相对简单执行。 注意:在本过程描述所有方向和方位将相对于外科医生。 <ol><li>请在Le切口从中线的≈5毫米右延伸胸骨切迹的VEL到≈左中线5毫米。 </li><li>使沿第一切口的右边缘延伸的第二切口，吻侧延伸到一个水平≈2毫米尾椎下颌骨的末尾。 </li><li>使第三切口，从切口第二的喙端延伸过左中线向≈为5mm。缩回所得皮瓣向左以暴露下层组织。 </li><li>在钝性分离中线分开腮腺及颌下唾液腺。这将暴露底层肌肉组织覆盖气管。 </li><li>直截了当地分开以暴露气管右和左sternohyoideus肌肉。 </li><li>通过一个≈10厘米长3-0丝线缝合气管下，注意不包括食道。 </li><li>确定位置的气管切开术:仅仅尾椎喉部有第一气管环之前的差距，这是一个想法L存储单元进行气管切开术。 </li><li>调整所述歧管提供麻醉气体的呼吸机和打开呼吸机。 </li><li>通过用手指堵塞气管（ET）的管的尖端检查是否泄漏。确保≈10厘米水柱的气道压力。 </li><li>使用20号针头作为手术刀，切开气管。使切口比较宽，因为ET管将填补大部分气管腔。 </li><li>快速移动，取出面膜，小心地将ET管插入气管。不要强迫它作为组织是很脆弱的，并通过气管破壁可能导致气胸。 注意:立即在插入时，胸部应短途旅行变得明显。 </li><li>固定通气电路用胶带，以防止在ET管被拉出。 </li><li>在3-0缝线绑一个上手结，形成ET管周围的密封。 注意:此时胸部excursi附件应该是显而易见的。如果没有它通常是ET管的，这是问题的气管内的定位。拉气管插管，并尝试重新定位，着眼于气管为导向的方向。 </li></ol></li><li> 颈静脉网站的制备 <ol><li>缩回左唾液腺喙-侧向暴露颈外静脉。 </li><li>平分瘦肌肉（sternomastoideus），包括与钝性分离静脉。这将暴露颈静脉的外表面。 </li><li>仔细理清组织的主要部分，但作为静脉壁非常薄必须谨慎使用。一旦这项工作完成，覆盖唾液腺颈静脉后保存它插管。 </li></ol></li><li> 开胸手术;进入胸膜间隙而不损害心脏或肺 <ol><li>除去多覆盖延伸的右边缘胸部皮肤原始皮肤切口至剑突的水平，然后在整个中线到左中线≈1.5厘米。 注:应通过外部乳腺血管，其可以是出血显著源切割时作出。切割之前烧灼这些船只将在很大程度上防止这种出血。 </li><li>使用钝性分离，收回皮瓣横向暴露底层肌肉。 </li><li>隔离在右侧邻近使用血管扩张镊子胸骨尾侧方面胸大肌的插入。烧灼并切断肌肉。 </li><li>通过沿其附着到胸骨胸大肌切断。烧灼切割边缘，以确保止血。 </li><li>下一个破坏在同一侧的背阔肌，这是一个大张肌的覆盖鼠标的外侧面。烧灼和切这块肌肉，然后缩回切口处头侧。这可能需要一些生硬解剖。 注意:肋现在显而易见和心脏也可能在某些小鼠品系可见。在大多数的小鼠，在第四肋间尾半进入胸腔将提供对心脏很方便。第四肋间是第二个最尾的空间。 </li><li>要进入胸部，使用一对锋利的钳通过肋间肌肉层认真剖析了下来。 </li><li>一旦胸腔空间已经打开，小心地插入钝头血管扩张器。使用容器扩张器提供胸壁温和向上的力量，用钝端弹簧剪刀小心地切开肋间肌肉的剩余部分。 </li><li>一是横向切割，小心不要切断肺叶下方。接下来内侧延长切口，但停留3 - 中线4毫米横向避免乳内动脉。 注:乳内血管胸骨平行并且可导致显著失血如果切意外。 </li><li>仔细烧灼肋间肌的切割边缘，用小棉签向上滚动的组织，以便与切割组织烧灼接触而不与肺部或心脏接触。 </li><li>将盐水浸湿的棉花小朝通过中线指向切口倾斜涂药。提供一个温和向上的牵引，从底层结构拉胸壁路程。开始在切口的内侧边缘烧灼胸壁和结束左侧中线≈1厘米外侧。 </li><li>推进涂抹到左侧，使其始终保持在烧灼冰山下。 </li><li>一旦组织彻底烧灼，用剪刀通过胸骨经过精心切割的。心脏的顶点应该是在这一点上清晰可见。 </li><li>使用钝性分离，扰乱心包，并确定尾腔静脉。 </li><li>检查是否有出血的迹象，现在烧灼它。一旦所有出血已得到解决，小心地取出任何立体裁剪，烧灼接地垫，和生理盐水浸湿的纱布。 </li></ol></li><li> 放置颈静脉导管 <ol><li>连接在步骤1.6.2至通过在30号针头小心滑动管含有10％白蛋白的注射器所作的导管。 </li><li>开始通过导管注入的白蛋白。 </li><li>定向导管使得针在于在其自身的颈静脉，用针斜面向上。如果有必要，用针持有人在管旋转针头斜面移动到正确的方向。 </li><li>当导管完全冲洗停止输液。 </li><li>抓住用钳子导管针。用另一只手，用组织钳缩回唾液腺，以允许颈静脉的可视化。轻轻牵引周围远端颈组织静脉产生对血管壁的张力。使用方法浅的角度，仔细针头插入静脉。超前的3针针尖 - 4 mm产品进入血管。 </li><li>释放导管针固定的导管用一块胶带之前，这将限制针的任何运动一次释放。 </li><li>释放针并轻轻向后拉对针筒柱塞以确认该导管是在容器的腔，在该行可视化的血液。 </li><li>一旦定位正确固定导管与手术胶水在针附着到底层唾液腺。 </li><li>计算的总体积要输注。如果有不显著失血5微升/ g体重的体积是足够的。如果有显著失血注入6 - 6.5微升/ g的可能需要。设置流率，使得整个输液将在10个完整的 - 15分钟。 </li></ol></li><li> PV导管放置在左心室<ol><li>在上述外科手术过程中，放置光伏导管在含有生理盐水溶液的注射器，以允许它达到平衡。 </li><li>之前，为了安置，将注射器和导管旁边的鼠标。与在大致相同的高度的心脏导管尖端，零压力读数。 </li><li>用盐水浸泡小棉签，机动的心脏，让顶点的可视化。 </li><li>用25号针头，使刺切口尽可能靠近顶点尽可能的中心。 </li><li>以下在除去针，迅速通过切口插入导管。它并不需要多大的力来插入导管，所以推进导管入脑室时表现出克制。偶尔需要执行附加的刺切口。如果这是必要的，尽量靠近的初始位置执行后续切口，以尽量减少对心脏的损伤。 不E:一旦导管被推进到心室的最终位置是非常重要的。心室压力跟​​踪将通过低舒张压（&lt;10毫米汞柱）和高收缩压是明显的（&gt;在此点80毫米汞柱）。理想情况下，该导管将与刚刚脑室内外部电极心室居中。在导管位置的微调可通过观察光伏环路数据，寻找一个箱形追踪与侧面之间≈90°的角度来执行。 </li></ol></li></ol> 3.程序细节 注意:一旦导管就位简要稳定期（10 - 15分钟）是必要的，让动物从一些急性手术应激中恢复，并允许时间为流体的输注。在此之后的稳定期的实际协议就可以开始。 <ol><li>一旦光伏导管放置和手术操作已经停止，调低异氟醚≈1％作为麻醉的深刻手术飞机的需求正在减少。 <ol><li>在此期间，仔细监测鼠标以确保麻醉的适当电平被维持。仔细评估任何运动;呼吸肌的运动表明通气不足的电平，并可以通过提高呼吸的呼吸速率来解决。四肢或晶须的抽动运动迹象表明，老鼠越来越太轻，需要更多的麻醉剂。 注意:有各种各样的，可以结合该协议被用来治疗排列。许多这些治疗需要的药物输注。它有效地管理死空间体积是必不可少的。溶液交换机可以通过从一个注射泵向其他的针滑动的导管来实现。不久，早期输液结束前这么做是允许的导管被装与下一个的药物。有必要知道导管管道内的体积，以确定溶液开关的定时。引入在该行的小气泡的允许确定输液开关的精确定时;该气泡注入静脉循环的耐受性良好。 </li></ol></li><li>改变通过降低负荷和后负荷增加心脏的负荷条件。 <ol><li>通过阻断静脉回流到心脏前负荷降低。在此制备，可视化和随着从膜片到心脏通过阻塞尾部腔静脉。平滑且相对快速地执行该闭塞，持续不超过2 - 3秒。 2秒 - 通过执行一个温柔的腹部压迫持续1瞬时增加左室后负荷。 </li><li>在这些变化在心脏负荷，暂停呼吸，消除呼吸机引入的任何神器。 </li></ol></li><li>使用校准第体积信号Ë电导导管。这些过程是不必要的，使用导纳技术导管。 <ol><li>实验方案后注入5 - 10微升高渗盐水（20％NaCl）中的计算出并联电导。 </li><li>由取出导管和从左心室采血到肝素化的注射器采集血液。将此血液进入已知体积的比色杯中，并使用导管来测量电导。 </li><li>使用比色皿电导措施的电导信号转换成体积和并联电导必要定义由导管测量的绝对体积。 </li></ol></li><li>一旦该协议完成后，通过除去心脏下列腔静脉和主动脉附件的横断安乐死鼠标。 </li></ol>

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The author has nothing to disclose.

有在此过程中三个关键步骤:1）气管导管和适当的通风，2）颈静脉导管的安置，以及3）在左心室光伏导管的正确放置的位置。确定适当的呼吸频率提供通气支持的重要组成部分。清醒小鼠一般保持快速浅呼吸肺泡通气。一般情况下，通风老鼠将有更大的潮气量。从而较慢的呼吸速率是必需的。这很重要，因为太少的通风会导致呼吸性酸中毒和太多的通风会导致呼吸性碱中毒，这两个条件，这将改变心脏功能。优化呼吸频率的一个简单的方法是从鼠标的呼吸努力采取暗示和使用消除了麻醉小鼠呼吸费力的最低呼吸频率。 光伏循环的关键特征分析是维持麻醉的足够水平的无心脏功能的显著抑郁症。有迹象表明，可以成功地应用于进行PV回路分析许多麻醉政权。这些可以分为两大类:吸入和注射麻醉剂。在该后一组有各种可使用的混合物，然而，许多这些混合物的具有潜在的心抑郁效应19。注射鸡尾酒，聚氨酯麻醉药有最少的心抑郁症的效果4,19。照顾到限制人员暴露于氨基甲酸酯，因为它是一种可疑的致癌物28。异氟醚和七氟醚是当前可用的吸入麻醉剂。这两种药都在足够手术操作剂量心抑郁的效果。重要的是，吸入麻醉剂可滴定到效果。这允许手术准备，​​然后低级塞达特期间更高的镇痛剂量IVE剂量为心脏功能的测量，从而减少了这些化合物的心抑郁作用。 如果血液动力学参数是低于正常水平，有几种常见原因。首先是低血容量，继发失血或蒸发。这种并发症通常与2.7节中概述的流体管理处理。正如在1.5节所述，核心体温的维护也是血液动力学功能的评估非常重要。因此仔细监测是必要的，一个数字反馈系统可以用于记录期间保持核心体温是有用的。确保麻醉剂已经在测量阶段被适当降低还改善心脏性能的一个重要方面。 测量收缩的负载无关的参数是光伏环分析的主要优点之一。的压力和体积的实时同步​​采集UME提供的数据来衡量对心脏变负载条件下响应血流动力学变化的独特能力。此分析使心脏的收缩功能从船只的行为进行分离。在预压减少通过静脉回流阻塞已被用来评估收缩的负载无关的措施在许多动物模型和人4,7,12-16,18,29-32。在小老鼠，这个过程导致曲线收缩末期压力容积关系4,31,33。从冠脉灌注减少，极大地加速了收缩功能的34下降这可能结果。在小鼠中，2 - 在PV的右移3秒的温和腹部压缩结果循环。这是由于既增加后负荷和预紧12。延长的增加收缩功能在后负荷结果增加时，一个现象称为Anrep效果35。然而，在这些研究中所用的腹部压缩的短持续时间表明Anrep效应不影响心脏功能这一步骤。在其他研究中，在犬急性主动脉缩窄被证明增加收缩功能，但这种推测从减少全身灌流36的影响造成的。再次的持续时间，并从腹部压缩所得，如这里所描述主动脉血流的破坏的严重性，不足以显著增加收缩功能继发于全身组织的低灌注。通过腹部的压缩获得PV循环分析尾腔静脉阻塞后不久获得的PV循环排列好。总之，这些观察结果表明，这里所描述的瞬态腹部压缩不显著改变心脏的收缩性。此外，该程序提供了一个重要的方法在更宽跑到评估心脏的被动属性舒张末期容积的GE。 的负载无关的措施的分析需要特定的PV的选择循环，以被包含在分析中。它是非常重要的，这可以在整个实验数据集一致完成。正压通气通过创建预紧左心室37呼吸系统相关的改变血流动力学的神器。 （ - 4秒3）为了避免这种神器，PV环应在呼吸暂停的时间很短收集。因为它们提供了对心脏加载实验性的变更更好地控制呼吸暂停特别有用。重要的是要保持短以避免低通气性呼吸暂停的这些周期是很重要的。在这个手稿中描述的过程，从两个不同的程序，尾腔静脉闭塞和腹部的压缩，在大致相同的时间收集收集负载无关的数据。来自这两个过程中分离出的环应合并和磕磕碰碰分析呃，因为它们都测量同一心脏的作用下，大致在相同的条件。有几个原则进行分析选择循环时，需要考虑。避免心律失常的节拍。下面一拍下降的节拍总是异常大和早搏异常小;既会破坏数据的分析。避免次，其中的压力下降，但数量是恒定的。这些都是在尾部腔静脉闭塞以下鼠标常见并有可能继发于心肌的灌注不足。最后，包括装在变更后直接拍唯一的数据;在恢复期中的节拍很可能受交感神经活动的改变继发从心脏的负荷条件下操作导致全身血压的变化。 PV回路分析提供心脏功能的一个非常详细的评估。当与遗传挠曲施加结合ibility和鼠标的低外壳成本它可以提供在分子水平上评估心脏生理学的实际手段。有迹象表明，必须在决定进行这些试验时，需要考虑几个重要的限制。首先，这是一种侵入性过程，其中小鼠麻醉，这可能会影响心脏功能的重要方面。此外，PV环数据的解释，需要心脏生理都详细了解的数据和潜在的混杂变量中识别模式。此外，由于这些测定是终端它们不能被用于重复评估相同的鼠标。从光伏导管衍生的心室体积往往比通过MRI提供解剖心室容积不太准确。这并不奇怪，因为光伏导管心室为一筒，这显然是心室的总体积的估计值进行建模。真正的力量是在一个较高的FRE收集本卷信息的能力昆西，因此允许在心室体积变化的搏动到节拍分析。 收集和从鼠标光伏数据的分析可以是具有挑战性的，但该方法对于心功能不可用通过任何其他方法提供信息。此过程提供心脏功能最完整的画面，并提供了其在小鼠模型中的利用率将提供复杂心脏疾病的分子基础的决心的重要平台，如心脏衰竭和心肌病遗传。这份手稿提供了有关执行此过程中最关键的环节的详细信息。然而，像所有的复杂的程序，这需要实践来构建显微技能所必需的成功执行这些实验。

心血管疾病仍然是世界各地的1死亡率和发病率的一个显著原因。心脏的疾病，目前在开发新的治疗特别困难的挑战。在遗传学的进展提供了识别潜在的遗传贡献者多种心脏疾病发展的可能性。心血管系统的综合性质，要求这些遗传目标的完整的动物模型中进行验证。鼠标的遗传灵活性和低住房成本已经把它带到了最前沿的一个特定基因的生理作用的评估。鼠标的小尺寸提出了心脏功能评估一些独特的挑战。有几种方式，可以提供关于心脏功能的信息，但只有心室压力和体积的同时测量允许压力容积（PV）心室功能的循环分析。光伏全循环流心脏功能进行分析独立于其连接到脉管的;在确定特定遗传元件的功能作用的重要因素。 压力-体积环的评估已经用于实验和临床上多年和广泛的文献存在对这些数据的分析台2,3。光伏循环技术的鼠标适配一直小鼠心脏生理4-6的理解的重要进展。基于导管的光伏循环技术对夫妇一个压力传感器和采用电导估计心室容积。心室体积是通过检查在由导管产生的电场的变化来确定。心室为圆柱体，它的高度由在导管和半径电极之间的距离所限定的本方法的模型是由电场的传导通过血液中计算心室7-9。由导管测定的电导信号有两个分量。第一种是通过血液中的导通;这个变化与心室的体积，并构成用于确定心室体积的初级信号。第二成分通过，并沿着心室的壁由传导引起的。这就是所谓的并联电导，并且必须以确定的绝对心室容积中移除。有对压力-体积数据的在研究实验室的收集和用于计算和删除并行电导的方法两种市售系统在它们6,10,11之间的主要区别。电导导管需要高渗盐水的平行电导的计算的注入。此注入瞬时改变心室血液的导电性，而壁的导电性保持不变。从这个数据，可以判断从血液起源和什么电导信号的分量来自于室壁。这种方法假设平行电导不会在心动周期中发生变化。准入方法依赖于电场的相位变化来评估心室壁的整体音量信号的贡献。此方法依赖于多种用于血液和心肌确定最终体积的电导率预定常数，不过在心动周期中，使平行电导的连续的措施。这两个系统的提供左心室体积的良好估计和它们之间的差异不太可能是生理显著。心室和其他假设的圆柱模型渲染不一样准确其他方式这些基于导管的方法，但是这种数据设置在一个节拍逐节拍的基础是对心功能的负载独立措施的评价是至关重要的。 这里所概述的程序是在我的实验室中使用，并已进行了大量的研究探讨营养不良病12-18的基本病理生理机制提供的数据。下面概述的过程是一个可以被用于获得光伏环两个数据之一。虽然许多原则适用于任何一种方法，该协议将专注于开胸顶的方法;一个胸外协议已在别处19,20详细说明。而程序将详细描述的那样，重要的首要原则是与要么心脏或肺部损害最小暴露心脏。在整个协议的是要记住，这是一个非生存过程，并且具有一个心脏良好曝光为导管的正确放置极为重要的是非常重要的。

<table><tbody><tr><td>Dumont 5/45 (2)</td><td>Fine Science Tools</td><td>11251-33</td><td></td></tr><tr><td>Vessel Dilating Forceps</td><td>Fine Science Tools</td><td>18153-11</td><td></td></tr><tr><td>Castroviejo Micro Dissecting Spring Scissor</td><td>Roboz Instruments</td><td>RS-5668</td><td></td></tr><tr><td>Octogon Forceps - Serrated/Curved</td><td>Fine Science Tools</td><td>11041-08</td><td></td></tr><tr><td>Octogon Forceps - Serrated/Straight</td><td>Fine Science Tools</td><td>11040-08</td><td></td></tr><tr><td>Dissector Scissors- Heavy Blade</td><td>Fine Science Tools</td><td>14082-09</td><td></td></tr><tr><td>Transpore Surgical Tape</td><td>3M</td><td>1527-1</td><td></td></tr><tr><td>3-0 Silk Suture</td><td>Fine Science Tools</td><td>18020-30</td><td></td></tr><tr><td>TOPO Ventilator</td><td>Kent Scientific</td><td>TOPO</td><td></td></tr><tr><td>Martin ME 102 Electrosurgical Unit</td><td>Harvard Apparatus</td><td>PY2 72-2484</td><td></td></tr><tr><td>Syringe Pump</td><td>Lucca Technologies</td><td>GenieTouch</td><td></td></tr><tr><td>Stereomicroscope with boom stand</td><td>Nikon</td><td>SMZ-800N</td><td></td></tr><tr><td>Thermocouple Thermometer</td><td>Cole Parmer</td><td>EW-91100-40</td><td></td></tr><tr><td>T/Pump Warm Water Recirculator</td><td>Kent Scientific</td><td>TP-700</td><td></td></tr><tr><td>ADVantage Pressure-Volume System</td><td>Transonic</td><td>ADV500</td><td></td></tr><tr><td>Data Acquision and Analysis</td><td>DSI</td><td>Ponemah ACQ-16</td><td></td></tr></tbody></table>

measuring pressure volume loops in the mouse

理解的原因和心脏疾病的进展呈现给生物医学界一个显著挑战。鼠标的遗传灵活性提供了很大的潜力在分子水平上，以探索心脏功能。鼠标的体积小巧确实提供的问候一些挑战进行详细的心脏表型。小型化和技术进步等已在小鼠心脏评估可能的方法很多。在这些中，压力和体积的数据的同时集合提供心脏功能的详细的图片是不通过任何其他方式。此处压力 - 容积环数据的收集的详细过程进行说明。包括的是的测量和误差的潜在来源的基本原则的讨论。麻醉管理和手术方法非常详细，因为他们是获得高质量的血流动力学测量两个关键的讨论秒。血流动力学协议开发和数据分析的相关方面的原则也被解决。

按照惯例，体积绘制在X轴和压力对Y轴如图1中。从对体积绘制压力产生应类似于一个矩形的压力-容积环，代表在压力（等容的变化，即在垂直的边缘，当两个二尖瓣和主动脉阀关闭）。底部水平代表心室通过二尖瓣和上部水平部填充代表心室通过主动脉瓣排空。在90健康的野生型小鼠左心室压力- 110毫米汞柱，预计8000的最大DP / DT - 12000毫米汞柱/秒（见的正常血流动力学参数范围见表1）。在表中提供的正常范围是基于来自野生型C57BL / 10和C57BL / 6小鼠获得的值;然而，需要注意的是有菌株21之间显著差异是重要的。该方法O这里utlined侧重于使用心尖刺切口到左心室内定位导管。另一种流行的方法是插入通过主动脉瓣以下在右颈动脉导管插入逆行导管。逆行法中，它可以与封闭胸腔中进行，从而在维持正常的胸内压力的优点;然而，将动物经常此过程，它限制了这种优点期间换气。胸外方法限制控制心室中导管的方向，而开胸方法提供给心室内操纵导管更大的能力。与导管的逆行插入的潜在问题是为流出轨道阻塞的可能性。鼠标主动脉的直径变化从0.8毫米至1.2毫米22,23，市售压力-容积的导管的直径范围为0.33（1.0法语）至0.47毫米（1.4 FRENCH​​）。在一个大的和小的主动脉的上下文中这些导管的相对尺寸在图2中描绘的阻塞导管横过主动脉流出道的分数可以成为较小心中显著问题并执行时，应考虑到小光伏心中循环研究。有测量的多个工件，可以是导管包封光伏数据时，最常见的一种的分析复杂化。此作为在收缩的端部由心室内的乳头肌或其他动态结构（ 图3）从压力传感器的直接压缩可能导致压力尖峰是显而易见的。这是有问题的，因为用于确定收缩功能的大多数方法使用的最大压力。从数据集与导管包封收缩压和压力最大衍生物（DP / dt的）需要密切观察和分析可能需要改变，以获得有意义的数据。 压力 - 容积环可在广泛多种协议可以用来评估心脏功能。这些措施包括通过β肾上腺素能刺激12,14,16,17心脏储备的评估。各种各样的药物可输注以评估心脏生理任何急性效果。气道的控制也允许改变气体混合物使缺氧和/或酸中毒对心脏功能的影响的管理直接24-27处理。此外，该光伏数据的分析还可以提供左心室的被动性质，其可以显著在各种疾病状态12改变的详细评估。 <table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always"><tbody><tr><td> 参数 </td><td> 普通范围 </td></tr><tr><td>收缩压</td><td> 90 - 110毫米汞柱</td></tr><tr><td>舒张压</td><td> 4 - 10毫米汞柱</td></tr><tr><td>最大DP / DT </td><td> 8000 - 12000毫米汞柱/秒</td></tr><tr><td>最小DP / DT </td><td> -8,500 - -12,000毫米汞柱/秒</td></tr><tr><td>牛头</td><td> 5 - 6秒</td></tr><tr><td>心率</td><td> 550 - 600 BPM </td></tr><tr><td>心输出量</td><td> 10 - 13毫升/分钟</td></tr><tr><td>射血分数</td><td> 40 - 60％的</td></tr></tbody></table> 表1.正常值为选定的血流参数。 <img alt="图1" src="/files/ftp_upload/53810/53810fig1.jpg" /> 图1:从使用的程序收集在THI记载的野生型C57BL / 10小鼠代表数据代表压力-容积环手稿。 <a href="https://www-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/53810/53810fig1large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图2" src="/files/ftp_upload/53810/53810fig2.jpg" /> 图2:主动脉直径及潜在流出轨道梗阻的重要性的示意图鼠标主动脉的相对尺寸和小鼠市售压力-体积的导管的示意图。这些数据凸显考虑流出赛道障碍物评估利用逆行导管插入方法小老鼠时的重要性。 <a href="https://www-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/53810/53810fig2large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图3" src="/files/ftp_upload/53810/53810fig3.jpg" /> <str翁&gt;图3:压力容积环与导管包封这些数据代表了一个压力峰值的一个例子在后期收缩，由内部心脏结构从导管的直接压缩可能产生的。下降在舒张末期容积（A）的结果的增加的压力峰值为心室变小，但收缩压代表之前的峰值跌幅如预期的那样，被描绘为在二（C和D）中的虚线的以下腹部压缩压力 - 容积环（C）和压力 - 时间（D）的曲线。作为左心室容积增大，压力尖峰变得更小，并在收缩功能的底层增加变得明显;在D.虚线<a href="https://www-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/53810/53810fig3large.jpg" target="_blank">请点击此处查看该图的放大版本。</a>

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Measuring Pressure Volume Loops in the Mouse

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测量压力容量环中的鼠标

Understanding the causes and progression of heart disease presents a significant challenge to the biomedical community. The genetic flexibility of the ...

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视频: Measuring Pressure Volume Loops in the Mouse

Measuring Left Ventricular Pressure in Late Embryonic and Neonatal Mice

Blood pressure increases significantly during embryonic and postnatal development in vertebrate animals. In the mouse, blood flow is first detectable around embryonic day (E) 8.51. Systolic left ventricular (LV) pressure is 2 mmHg at E9.5 and 11 mmHg at E14.52. At these mid-embryonic stages, the LV is clearly visible through the chest wall for invasive pressure measurements because the ribs and skin are not fully developed. Between E14.5 and birth (approximately E21) imaging methods must be used to view the LV. After birth, mean arterial pressure increases from 30 - 70 mmHg from postnatal day (P) 2 - 353. Beyond P20, arterial pressure can be measured with solid-state catheters (i.e. Millar or Scisense). Before P20, these catheters are too big for developing mouse arteries and arterial pressure must be measured with custom pulled plastic catheters attached to fluid-filled pressure transducers3 or glass micropipettes attached to servo null pressure transducers4.
Our recent work has shown that the greatest increase in blood pressure occurs during the late embryonic to early postnatal period in mice5-7. This large increase in blood pressure may influence smooth muscle cell (SMC) phenotype in developing arteries and trigger important mechanotransduction events. In human disease, where the mechanical properties of developing arteries are compromised by defects in extracellular matrix proteins (i.e. Marfan's Syndrome8 and Supravalvular Aortic Stenosis9) the rapid changes in blood pressure during this period may contribute to disease phenotype and severity through alterations in mechanotransduction signals. Therefore, it is important to be able to measure blood pressure changes during late embryonic and neonatal periods in mouse models of human disease.
We describe a method for measuring LV pressure in late embryonic (E18) and early postnatal (P1 - 20) mice. A needle attached to a fluid-filled pressure transducer is inserted into the LV under ultrasound guidance. Care is taken to maintain normal cardiac function during the experimental protocol, especially for the embryonic mice. Representative data are presented and limitations of the protocol are discussed.

Measuring left ventricular pressure (LV) in embryonic and neonatal mice is described. Pressure is measured by inserting a needle connected to a fluid-filled transducer into the LV under ultrasound guidance. Care must be taken to maintain normal cardiac function during the experimental protocol.

测量中晚期胚胎和新生小鼠左心室压力

Blood pressure increases significantly during embryonic and postnatal development in vertebrate animals. In the mouse, blood flow is first detectable ...

科研

生物工程

Right Ventricular Systolic Pressure Measurements in Combination with Harvest of Lung and Immune Tissue Samples in Mice

The function of the right heart is to pump blood through the lungs, thus linking right heart physiology and pulmonary vascular physiology. Inflammation is a common modifier of heart and lung function, by elaborating cellular infiltration, production of cytokines and growth factors, and by initiating remodeling processes 1.
Compared to the left ventricle, the right ventricle is a low-pressure pump that operates in a relatively narrow zone of pressure changes. Increased pulmonary artery pressures are associated with increased pressure in the lung vascular bed and pulmonary hypertension 2. Pulmonary hypertension is often associated with inflammatory lung diseases, for example chronic obstructive pulmonary disease, or autoimmune diseases 3. Because pulmonary hypertension confers a bad prognosis for quality of life and life expectancy, much research is directed towards understanding the mechanisms that might be targets for pharmaceutical intervention 4. The main challenge for the development of effective management tools for pulmonary hypertension remains the complexity of the simultaneous understanding of molecular and cellular changes in the right heart, the lungs and the immune system.
Here, we present a procedural workflow for the rapid and precise measurement of pressure changes in the right heart of mice and the simultaneous harvest of samples from heart, lungs and immune tissues. The method is based on the direct catheterization of the right ventricle via the jugular vein in close-chested mice, first developed in the late 1990s as surrogate measure of pressures in the pulmonary artery5-13. The organized team-approach facilitates a very rapid right heart catheterization technique. This makes it possible to perform the measurements in mice that spontaneously breathe room air. The organization of the work-flow in distinct work-areas reduces time delay and opens the possibility to simultaneously perform physiology experiments and harvest immune, heart and lung tissues.
The procedural workflow outlined here can be adapted for a wide variety of laboratory settings and study designs, from small, targeted experiments, to large drug screening assays. The simultaneous acquisition of cardiac physiology data that can be expanded to include echocardiography5,14-17 and harvest of heart, lung and immune tissues reduces the number of animals needed to obtain data that move the scientific knowledge basis forward. The procedural workflow presented here also provides an ideal basis for gaining knowledge of the networks that link immune, lung and heart function. The same principles outlined here can be adapted to study other or additional organs as needed.

A specific and rapid protocol to simultaneously investigate right heart function, lung inflammation, and the immune response is described as a learning tool. Video and figures describe physiology and microdissection techniques in an organized team-approach that is adaptable to be used for small to large sized studies.

右心室收缩压测量组合在小鼠的肺和免疫组织样品的收获

The function of the right heart is to pump blood through the lungs, thus linking right heart physiology and pulmonary vascular physiology. Inflammation is ...

免疫与感染

Measuring Blood Pressure in Mice using Volume Pressure Recording, a Tail-cuff Method

The CODA 8-Channel High Throughput Non-Invasive Blood Pressure system measures the blood pressure in up to 8 mice or rats simultaneously. The CODA tail-cuff system uses Volume Pressure Recording (VPR) to measure the blood pressure by determining the tail blood volume. A specially designed differential pressure transducer and an occlusion tail-cuff measure the total blood volume in the tail without the need to obtain the individual pulse signal. Special attention is afforded to the length of the occlusion cuff in order to derive the most accurate blood pressure readings. VPR can easily obtain readings on dark-skinned rodents, such as C57BL6 mice and is MRI compatible. The CODA system provides you with measurements of six (6) different blood pressure parameters; systolic and diastolic blood pressure, heart rate, mean blood pressure, tail blood flow, and tail blood volume. Measurements can be made on either awake or anesthetized mice or rats. The CODA system includes a controller, laptop computer, software, cuffs, animal holders, infrared warming pads, and an infrared thermometer. There are seven different holder sizes for mice as small as 8 grams to rats as large as 900 grams.

The CODA 8-Channel High Throughput Non-Invasive Blood Pressure system measures the blood pressure in up to 8 mice or rats simultaneously. This tail-cuff system uses Volume Pressure Recording (VPR) to measure the blood pressure by determining the tail blood volume.

使用卷压力记录，一条尾巴袖套法小鼠的血压测量

The CODA 8-Channel High Throughput Non-Invasive Blood Pressure system measures the blood pressure in up to 8 mice or rats simultaneously. The CODA ...

生物学

Catheterization of Intestinal Loops in Ruminants

The intestine is a complex structure that is involved not only in absorption of nutrients, but also acts as a barrier between the individual and the outside world. As such, the intestine plays a pivotal role in immunosurveillance and protection from enteric pathogens. Investigating intestinal physiology and immunology commonly employs 'intestinal loops' as an experimental model. The majority of these loop models are non-recovery surgical procedures that study short-term (&lt;24 hr) changes in the intestine (1-3). We previously created a recovery intestinal loop model to specifically measure long-term (&lt;6 mo) immunological changes in the intestine of sheep following exposure to vaccines, adjuvants, and viruses (4). This procedure localized treatments to a specific 'loop', allowing us to sample this area of the intestine. A significant drawback of this method is the single window of opportunity to administer treatments (i.e. at the time of surgery). Furthermore, samples of both the intestinal mucosa and luminal contents can only be taken at the termination of the project. Other salient limitations of the above model are that the surgical manipulation and requisite post-operative measures (e.g. administration of antibiotics and analgesics) can directly affect the treatment itself and/or alter immune function, thereby confounding results. Therefore, we modified our intestinal loop model by inserting long-term catheters into the loops. Sheep recover fully from the procedure, and are unaffected by the exteriorized catheters. Notably, the establishment of catheters in loops allows us to introduce multiple treatments over an extended interval, following recovery from surgery and clearance of drugs administered during surgery and the post-operative period.

We describe a novel surgical method for catheterizing 'intestinal loops' within the ileum of sheep. Once animals have recovered from surgery and have cleared antibiotics and analgesics, multiple treatments can be deposited directly in loops via the catheters.

导尿在反刍动物的肠袢

The intestine is a complex structure that is involved not only in absorption of nutrients, but also acts as a barrier between the individual and the ...

Measurement of the Pressure-volume Curve in Mouse Lungs

In recent decades the mouse has become the primary animal model of a variety of lung diseases. In models of emphysema or fibrosis, the essential phenotypic changes are best assessed by measurement of the changes in lung elasticity. To best understand specific mechanisms underlying such pathologies in mice, it is essential to make functional measurements that can reflect the developing pathology. Although there are many ways to measure elasticity, the classical method is that of the total lung pressure-volume (PV) curve done over the whole range of lung volumes. This measurement has been made on adult lungs from nearly all mammalian species dating back almost 100 years, and such PV curves also played a major role in the discovery and understanding of the function of pulmonary surfactant in fetal lung development. Unfortunately, such total PV curves have not been widely reported in the mouse, despite the fact that they can provide useful information on the macroscopic effects of structural changes in the lung. Although partial PV curves measuring just the changes in lung volume are sometimes reported, without a measure of absolute volume, the nonlinear nature of the total PV curve makes these partial ones very difficult to interpret. In the present study, we describe a standardized way to measure the total PV curve. We have then tested the ability of these curves to detect changes in mouse lung structure in two common lung pathologies, emphysema and fibrosis. Results showed significant changes in several variables consistent with expected structural changes with these pathologies. This measurement of the lung PV curve in mice thus provides a straightforward means to monitor the progression of the pathophysiologic changes over time and the potential effect of therapeutic procedures.

Here we present a protocol to simply and reliably measure the lung pressure-volume curve in mice, showing that it is sufficiently sensitive to detect phenotypic parenchymal changes in two common lung pathologies, pulmonary fibrosis and emphysema. This metric provides a means to quantify the lung&#8217;s structural changes with developing pathology.

在小鼠肺压力容积曲线的测量

In recent decades the mouse has become the primary animal model of a variety of lung diseases. In models of emphysema or fibrosis, the essential ...

医学

Cardiac Catheterization in Mice to Measure the Pressure Volume Relationship: Investigating the Bowditch Effect

Animal models that mimic human cardiac disorders have been created to test potential therapeutic strategies. A key component to evaluating these strategies is to examine their effects on heart function. There are several techniques to measure in vivo cardiac mechanics (e.g., echocardiography, pressure/volume relations, etc.). Compared to echocardiography, real-time left ventricular (LV) pressure/volume analysis via catheterization is more precise and insightful in assessing LV function. Additionally, LV pressure/volume analysis provides the ability to instantaneously record changes during manipulations of contractility (e.g., &#946;-adrenergic stimulation) and pathological insults (e.g., ischemia/reperfusion injury). In addition to the maximum (+dP/dt) and minimum (-dP/dt) rate of pressure change in the LV, an accurate assessment of LV function via several load-independent indexes (e.g., end systolic pressure volume relationship and preload recruitable stroke work) can be attained. Heart rate has a significant effect on LV contractility such that an increase in the heart rate is the primary mechanism to increase cardiac output (i.e., Bowditch effect). Thus, when comparing hemodynamics between experimental groups, it is necessary to have similar heart rates. Furthermore, a hallmark of many cardiomyopathy models is a decrease in contractile reserve (i.e., decreased Bowditch effect). Consequently, vital information can be obtained by determining the effects of increasing heart rate on contractility. Our and others data has demonstrated that the neuronal nitric oxide synthase (NOS1) knockout mouse has decreased contractility. Here we describe the procedure of measuring LV pressure/volume with increasing heart rates using the NOS1 knockout mouse model.

This article describes the measurement of murine left ventricular function via pressure/volume analysis at different heart rates.

心导​​管在小鼠测量压力体积的关系:调查的影响鲍迪奇

Animal models that mimic human cardiac disorders have been created to test potential therapeutic strategies. A key component to evaluating these ...

Biventricular Assessment of Cardiac Function and Pressure-Volume Loops by Closed-Chest Catheterization in Mice

Assessment of cardiac function is essential to conduct cardiovascular and pulmonary-vascular preclinical research. Pressure-volume loops (PV loops) generated by recording both pressure and volume during cardiac catheterization are vital when assessing both systolic and diastolic cardiac function. Left and right heart function are closely related, reflected in ventricular interdependence. Thus, recording biventricular function in the same animal is important to get a complete assessment of cardiac function. In this protocol, a closed chest approach to cardiac catheterization consistent with the way catheterization is performed in patients is adopted in mice. While challenging, the closed chest strategy is a more physiological approach, because opening the chest results in major changes in preload and afterload that create artifacts, most notably a fall in systemic blood pressure. While high-resolution echocardiography is used to assess rodents, cardiac catheterization is invaluable, particularly when assessing diastolic pressures in both ventricles.
Described here is a procedure to perform invasive, closed chest, sequential left and right ventricular pressure-volume (PV) loops in the same animal. PV loops are acquired using&#160;admittance technology with a mouse pressure-volume catheter and pressure-volume system acquisition. The procedure is described, beginning with the neck dissection, which is required to access the right jugular vein and the right carotid artery, to the insertion and positioning of the catheter, and finally the data acquisition. Then, the criteria required to ensure the acquisition of high-quality PV loops are discussed. Finally, the analysis of the left and right ventricular PV loops and the different hemodynamic parameters available to quantify systolic and diastolic ventricular function are briefly described.

Presented here is a protocol to assess biventricular heart function in mice by generating pressure-volume (PV) loops from the right and left ventricle in the same animal using closed chest catheterization. The focus is on the technical aspect of surgery and data acquisition.

小鼠闭胸导管插入术对心功能和压力-容积环的双心室评估

Assessment of cardiac function is essential to conduct cardiovascular and pulmonary-vascular preclinical research. Pressure-volume loops (PV loops) ...

Cardiac Response to &#946;-Adrenergic Stimulation Determined by Pressure-Volume Loop Analysis

Determination of the cardiac function is a robust endpoint analysis in animal models of cardiovascular diseases in order to characterize effects of specific treatments on the heart. Due to the feasibility of genetic manipulations the mouse has become the most common mammalian animal model to study cardiac function and to search for new potential therapeutic targets. Here we describe a protocol to determine cardiac function&#160;in vivo using pressure-volume loop measurements and analysis during basal conditions and under &#946;-adrenergic stimulation by intravenous infusion of increasing concentrations of isoproterenol. We provide a refined protocol including ventilation support taking into account the positive end-expiratory pressure to ameliorate negative effects during open-chest measurements, and potent analgesia (Buprenorphine) to avoid uncontrollable myocardial stress evoked by pain during the procedure. All together the detailed description of the procedure and discussion about possible pitfalls enables highly standardized and reproducible pressure-volume loop analysis, reducing the exclusion of animals from the experimental cohort by preventing possible methodological bias.

Here we describe a cardiac pressure-volume loop analysis under increasing doses of intravenously infused isoproterenol to determine the intrinsic cardiac function and the &#946;-adrenergic reserve in mice. We use a modified open-chest approach for the pressure-volume loop measurements, in which we include ventilation with positive end-expiratory pressure.

通过压力-体积环路分析确定心脏对β肾上腺素能刺激的反应

Determination of the cardiac function is a robust endpoint analysis in animal models of cardiovascular diseases in order to characterize effects of ...

Cardiac Pressure-Volume Loop Analysis Using Conductance Catheters in Mice

Cardiac pressure-volume loop analysis is the &#8220;gold-standard&#8221; in the assessment of load-dependent and load-independent measures of ventricular systolic and diastolic function. Measures of ventricular contractility and compliance are obtained through examination of cardiac response to changes in afterload and preload. These techniques were originally developed nearly three decades ago to measure cardiac function in large mammals and humans. The application of these analyses to small mammals, such as mice, has been accomplished through the optimization of microsurgical techniques and creation of conductance catheters. Conductance catheters allow for estimation of the blood pool by exploiting the relationship between electrical conductance and volume. When properly performed, these techniques allow for testing of cardiac function in genetic mutant mouse models or in drug treatment studies. The accuracy and precision of these studies are dependent on careful attention to the calibration of instruments, systematic conduct of hemodynamic measurements and data analyses. We will review the methods of conducting pressure-volume loop experiments using a conductance catheter in mice.

Cardiac pressure-volume loop analysis is the most comprehensive way to measure cardiac function in the intact heart. We describe a technique to perform and analyze cardiac pressure volume loops, using conductance catheters.

心脏压力容量环分析小鼠使用电导导管

Cardiac pressure-volume loop analysis is the &#8220;gold-standard&#8221; in the assessment of load-dependent and load-independent measures of ventricular ...

使用心房起搏方案探索 HR 依赖性心脏功能

A Pacing-Controlled Procedure for the Assessment of Heart Rate-Dependent Diastolic Functions in Murine Heart Failure Models

Heart failure with preserved ejection fraction (HFpEF) is a condition characterized by diastolic dysfunction and exercise intolerance. While exercise-stressed hemodynamic tests or MRI can be used to detect diastolic dysfunction and diagnose HFpEF in humans, such modalities are limited in basic research using mouse models. A treadmill exercise test is commonly used for this purpose in mice, but its results can be influenced by body weight, skeletal muscle strength, and mental state. Here, we describe an atrial-pacing protocol to detect heart rate (HR)-dependent changes in diastolic performance and validate its usefulness in a mouse model of HFpEF. The method involves anesthetizing, intubating, and performing pressure-volume (PV) loop analysis concomitant with atrial pacing. In this work, a conductance catheter was inserted via a left ventricular apical approach, and an atrial pacing catheter was placed in the esophagus. Baseline PV loops were collected before the HR was slowed with ivabradine. PV loops were collected and analyzed at HR increments ranging from 400 bpm to 700 bpm via atrial pacing. Using this protocol, we clearly demonstrated HR-dependent diastolic impairment in a metabolically induced HFpEF model. Both the relaxation time constant (Tau) and the end-diastolic pressure-volume relationship (EDPVR) worsened as the HR increased compared to control mice. In conclusion, this atrial pacing-controlled protocol is useful for detecting HR-dependent cardiac dysfunctions. It provides a new way to study the underlying mechanisms of diastolic dysfunction in HFpEF mouse models and may help develop new treatments for this condition.

作者聚焦:通过新型心房起搏方法研究小鼠模型中的 HR 依赖性心脏功能 

The present protocol describes obtaining the pressure-volume relationship through transesophageal pacing, which serves as a valuable tool in evaluating diastolic function&#160;in mouse models of heart failure.

测量压力容量环中的鼠标

摘要

探索更多视频

此视频中的章节

测量中晚期胚胎和新生小鼠左心室压力

右心室收缩压测量组合在小鼠的肺和免疫组织样品的收获

使用卷压力记录，一条尾巴袖套法小鼠的血压测量

导尿在反刍动物的肠袢

在小鼠肺压力容积曲线的测量

心导管在小鼠测量压力体积的关系:调查的影响鲍迪奇

小鼠闭胸导管插入术对心功能和压力-容积环的双心室评估

通过压力-体积环路分析确定心脏对β肾上腺素能刺激的反应

心脏压力容量环分析小鼠使用电导导管

用于评估小鼠心力衰竭模型心率依赖性舒张功能的起搏控制程序

测量压力容量环中的鼠标

摘要

探索更多视频

此视频中的章节

测量中晚期胚胎和新生小鼠左心室压力

右心室收缩压测量组合在小鼠的肺和免疫组织样品的收获

使用卷压力记录，一条尾巴袖套法小鼠的血压测量

导尿在反刍动物的肠袢

在小鼠肺压力容积曲线的测量

心导​​管在小鼠测量压力体积的关系:调查的影响鲍迪奇

小鼠闭胸导管插入术对心功能和压力-容积环的双心室评估

通过压力-体积环路分析确定心脏对β肾上腺素能刺激的反应

心脏压力容量环分析小鼠使用电导导管

用于评估小鼠心力衰竭模型心率依赖性舒张功能的起搏控制程序

心导管在小鼠测量压力体积的关系:调查的影响鲍迪奇