This work was supported by a National Heart, Lung, and Blood Institute grant 1RO1-HL-105296-01 (to D.E. Berkowitz) and an Australian Research Council Grant DP110101134 (to A. Avolio).

该协议已经被批准的机构动物护理和使用委员会在约翰·霍普金斯大学。 1.准备的解决方案，材料和动物<ol><li>制备300微克/毫升的溶液去氧肾上腺素（PE）和300微克/毫升溶液硝普钠（SNP）在0.9％盐水中。通过混合1毫升1000单位/毫升肝素到10ml的0.9％盐水中制备单独的肝素盐溶液。 注：药物应该是在室温下在使用前。 </li><li>使两个30国祥½“注射针头和PE 10聚乙烯管导管静脉输注药物。为了使导管，插入一个针入软管的一端。除去其它皮下注射针的针部并插入钝端插入管的另一端。附加导管以1ml注射器，并填写与肝素盐溶液导管。 </li><li>鼠标放置在麻醉诱导室Containing 2-2.5％异氟烷在100％的氧。离开鼠标的感应室，直到它反应迟钝对外界的刺激。 </li><li>从感应腔室中取出小鼠，并将其放置在加热的心电图（ECG）垫。维持动物在2％异氟醚。 </li><li>适用兽医软膏或盐溶液到该动物的眼睛，以防止在操作过程中干。 </li></ol> 2.插入导管的尾静脉<ol><li>由于尾静脉上尾部的两侧横向地位于，放置在其一侧的动物更好的访问。确保鼠标到ECG垫带。确保动物保​​持温暖，以促进尾静脉的血管扩张。 </li><li>使用一块硅橡胶管作为止血带，扎止血带绕尾的基部。扎止血带不够紧崩的静脉，但不足以切断动脉循环。经过2-3分钟，静脉应凸出而变得更加明显。 </li><li>轻轻一拉绷紧的尾巴。弯曲的尾部在用一只手的角度，并保持平行的针，以与其它的尾巴。皮尔斯其中尾部穿过皮肤进入静脉弯曲针。血液会推回到所述导管如果针插入静脉。 </li><li>放置一滴组织胶，其中所述针被插入到固定导管。取出止血带，并注入生理盐水少许阻力确认通畅。 </li></ol>通过股动脉插入3.血压导管<ol><li>将压力导管到30ml注射器充满蒸馏水和导管连接到压力控制部。泡导管在水中，接通电源后，30-45分钟期间设置和手术过程。 </li><li>将动物仰卧并用胶带它的爪子上的心电图垫。胸部和面积在股动脉申请脱毛霜。 <ol><li>等待3-5分钟，取出奶油和头发。日oroughly从胸部取出头发，防止超声波期间的文物。无论擦拭胸部和后肢地区用湿垫去除多余脱毛霜。 </li></ol></li><li>使用细剪刀，做一个切口在上述股动脉的位置的皮肤。解剖通过皮下脂肪组织，露出股动脉。股动脉被部分覆盖的腹部。用止血移动腹部而去。保持组织湿润通过用湿纱布覆盖，或替代地周期性地滴盐水超过它，以防止组织干燥。 </li><li>用细镊子，从动脉静脉丛分离的神经了。通过围绕动脉静脉丛鞘轻轻刺穿到动脉从静脉分离。通过动脉周围1缝合在近端和放置两个缝合在远端。 </li><li>牢固地结最远侧缝合停止远端的血流。用止血拉Proximal缝合暂时停止血流进入股动脉。使用microscissors做一个小切口插入股动脉。使近远端结切口。 </li><li>使用压力控制装置上的校准设置的数据采集软件校准到导管。切换压力控制单元回读换能器和平衡压力导管，以使导管输出0毫米汞柱，在装满水的注射器。 </li><li>插入导管进入股动脉。用一只手打开所述切口用细镊子和插入导管头部与另一方面的动脉。 <ol><li>结的导管导线围在中间缝合来固定导管进入动脉。放松近侧缝合并向前推进所述导管进入腹主动脉。结近侧缝合线，以进一步固定导管，并防止出血。 </li></ol></li><li>小心地移动心电图垫鼠标，压力导管和生理盐水syringe到超声成像阶段。血压导管连接到压力控制部。放置在注射器泵的盐水注射器。允许动物和导管，以平衡20分钟。 </li></ol> 4.测量主动脉内径过血压的范围<ol><li>减少异氟烷1.5％。纵向形象化升主动脉上使用长轴视图B模式。安装该换能器上的导轨系统，以使相同的视图被保持在实验的持续时间。 </li><li>在超声大型机，将M型光标置于主动脉的部分进行跟踪。跟踪随着使用M型心动周期主动脉直径变化。 </li><li>在注射器给PE溶液改变盐水并将注射器放入注射器泵。 <ol><li>记录M型在基线主动脉的压力。开始输注360微克/公斤/分钟，并注入1分钟主动脉压，达到平台期。对于25克鼠标，该做的本身相当于30微升/分钟。 </li><li>记录的M模​​式，然后停止输液，并等待2分钟，血压返回到基线。 </li></ol></li><li>低输注速率至240微克/千克/分钟。对于一个25克鼠标，该剂量相当于20微升/分钟。开始输液，注入1分钟的血压平稳，并记录M-模式。停止输液，并等待2分钟，血压返回到基线。 </li><li> 120微克/公斤，重复步骤4.4 /分钟PE（10微升/分钟的25克鼠标）。 </li><li>取代的PE用盐水和注入的盐水在用于360微克/公斤/分钟输注的速率（30微升/分钟为一个25克小鼠）。注入为2-3分钟，直到进一步输注不产生增加主动脉压和压力返回到基线。等待5分钟，使血压在基线稳定。 </li><li>与SNP更换盐水。 <ol><li>记录M型在基线主动脉的压力。开始输注在240微克/千克/分钟（20微升/分钟25克小鼠）和注入​​，持续1分钟。当主动脉压力达到一个高原，记录M-模式。停止输液，等待2分钟为血压回到基线。 </li></ol></li><li>低输注速率至120微克/千克/分钟（10微升/分钟25克鼠标）。开始输液，注入1分钟的血压平稳，并记录M-模式。停止输注并等待2分钟为血压回到基线。 </li><li> 60微克/千克，重复步骤4.8 / min的SNP（5微升/分钟25克鼠标）。 </li></ol> 5.终止实验<ol><li>安乐死的动物，增加异氟烷至4％。当呼吸速度减慢，一般在1-2分钟，通过削减用剪刀打开胸腔，暴露心脏的胸骨。 </li><li>掌握中等钳心脏和削减在升主动脉，用剪刀从体内切除它。 </li></ol>

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取直径测量在几个压力增量在宽范围的压力值是必需的压径关系精确表征。可药理学诱导的上下压力极限可通过实验组变化，但是理想的范围是约25毫米汞柱至125毫米汞柱舒张压和50毫米汞柱至200毫米汞柱收缩。 360微克/千克/分钟PE和240微克/千克的剂量/分钟的SNP通常引起的压力范围的限制。然而，剂量的PE的可提高到480微克/千克/分钟和SNP至360微克/千克/分钟，以验证该限制已经达到。聚乙烯和SNP的工作浓度可以降低到实现更精细的压力增量。随着直径将与主动脉压力变化，诱发动物和实验组之间相同的压力值是不重要的。 静脉和动脉插管可以在其他位置具有相同的OU进行tcomes。尾静脉插管可以是由于尾静脉小尺寸有挑战性。此外，尾静脉不在深色小鼠容易看见。股静脉可以插管作为替代。这条路线可能会更容易，因为股静脉是更容易获得。对于压力的​​导管插入，除了股动脉，导管可通过颈动脉插入。股动脉优选在颈动脉，但是，因为胸部区域保持完整的超声成像。股动脉插管可以更困难，因为股动脉越小。使用1.2˚F导管和引入所述导管在腹腔下方的近端股动脉将方便插管过程。放置几滴像利多卡因血管扩张剂的上股动脉或使用导管导引器还可以帮助扩大容器，以方便的导管插入。压力导管应处理，并使用根据制造商的说明。 主动脉内导管的位置并不需要是动物之间是一致的主动脉内的压力降是微不足道的。然而，将所述导管在腹主动脉可能更好，以尽量减少与胸主动脉的超声成像的干扰。一些超声大型机可以记录压力实时与M型跟踪，从而给出为对M模式测量每直径的压力的测量。不幸的是，因为那里的直径测量的位置不相同的位置，其中压力被记录时，记录在导管中的压力，并在升主动脉中的实际压力之间的滞后存在。其结果是，只有最大和最小直径的测量可用于数据分析。 该方法的主要限制是由在主动脉和移出ö移引入在测量的不确定性f显示心动周期中的超声平面。运动引入误差是通用于所有基于成像研究，包括MRI和CT。补偿策略包括使用的解剖特点来参考帧的运动18移位和数据处理过程中实现的。作为运动补偿的软件是不容易获得的，研究者必须警惕调整探针的位置来跟踪此消彼长的主动脉血压上升的位置和降低。直径测量也应当通过主动脉的中心截取。然而，确定的M型记录位置是否被通过中心可能难以判断超声波图像上，尤其是与主动脉换档位置。通过这些限制体现在分散的数据的程度， 如图6引入，如明显的不确定性。获得ascendi的纵向轴线的横截面的图像，而不是纳克主动脉可能是一个解决办法。不过，获得这一观点有时会更具挑战性，所产生的M型跟踪可以就不太清楚了。从B模式图像的横截面周长可被测量，而不是从对M模式图像的直径。然而，确定当最大和最小圆周已经实现将由B模式帧速率是有限的，可能更难以判断比在M模式。 制造的压径积多个测量和增加实验组的大小可以提高数据的准确性。的压径数据可以从沿着胸部的几个位置被收集。该协议将首先进行与探针放置在一个位置上的胸部。主动脉然后将可视化与探针放在另一个位置和反复的协议。 用来调制血压血管活性剂可能会影响主动脉平滑肌MUSC乐调，这反过来会影响刚度。然而，操纵通过静脉回流主动脉压力已经显示出产生在侵入性测量PWV作为药理操纵大鼠类似的变化。这些结果表明，输注血管活性药物作用主要是外周阻力动脉和不显著影响主动脉平滑肌音19。 该协议可以在大鼠进行了一些小的改动。之前申请脱毛霜胸口剃光。市售27国祥½“导管用于药物注射。用来调制主动脉压的药物的剂量是40次，80次和PE和40，80的120微克/千克/分钟，和120微克/千克/ SNP的分除了升主动脉，主动脉刚度区域差异可与该协议来确定。通过这种方法测得的区域刚度会比更精确了PWV的测量ARE从一个位置作为反对两个位置的PWV。然而，沿着主动脉的区域，可以使用这种技术来测量被限制为那些可以通过超声波来可视化。 弹性模量也可以从若能够获得壁厚测量通过该方法收集的数据计算出来的。准确的小鼠主动脉的体内测量是通过电流超声技术的分辨率极限的限制。超声技术的未来改进可以使体内的壁厚测量更可行。作为替代，厚度测量可以进行体外 。压力肌动描记将提供最精确的测量，因为厚度可以在每个压力增量来测量。

增加动脉硬化是心血管疾病的一个标志。老化1，吸烟2，糖尿病3，高脂血症4，和心血管疾病的其它危险因素已被证明能增加主动脉刚度。流行病学研究已经进一步证明主动脉刚度冠状动脉心脏疾病和中风发病的一个有力的独立预测因子，以及心血管事件和死亡率5-8的发生。由于增加了主动脉僵硬的临床和公共卫生意义的，目前的研究重点是了解背后血管硬化的发生和发展的机制。因此极大的兴趣存在于显影在心血管疾病的实验模型中血管硬度的准确测量。 的材料的硬度的特征可在于它的应力 - 应变关系和定量为弹性模汗国。线性弹性材料可逆变形和应力比例提高应变。主动脉和大动脉是非线性弹性体：拉伸时，在动脉的刚度不会保持恒定，但具有腹胀的程度增大。这种非线性在大动脉的机械性能是由于在承载元件，即弹性蛋白和胶原蛋白，构成容器壁的不同的刚度特性。弹性是0.6兆帕的弹性模量高可扩展性。相比较而言，胶原蛋白是非常僵硬的为1GPa 9的弹性模量。在较低的应变值显示出由主动脉初始刚度是由于弹性而高刚度显示出在高应变值是由于胶原蛋白。载荷从弹性蛋白胶原转移作为容器distends和负载的该区域转移是其中血管系统进行操作。因此，在生理压力，动脉硬度取决于这两个弹性蛋白和胶原蛋白10的贡献。 的分布和弹性蛋白和胶原蛋白的取向由动脉壁内层而有所不同。在媒体中，弹性蛋白，胶原和平滑肌细胞被捆绑成紧螺旋是层状同心。这种布置允许在动脉抵抗高负荷在圆周方向上。外膜主要是胶原蛋白与小弹性蛋白和胶原纤维被组织在一个网状方式。这些胶原纤维波浪在无应力状态，理顺随着负载的增加。刚度随着胶原纤维理顺，从而防止动脉从过度拉伸和破裂。由于胶原纤维的结构组织和不同取向的，动脉是各向异性：表现出刚度取决于如果容器被纵向或周向11拉伸体内 stiffnes。因此s是主动脉的纵向和周向刚性的复合材料。 动脉僵硬度一般是量化体内的合规性和脉搏波速度（PWV）。动脉顺应性被定义为C =ΔD/ΔP其中ΔD是变化的直径和ΔP是在压力的相应变化。达标值越低表明硬的船只。遵从动脉的压力 - 维关系计算，因此直接测量刚度。如刚度在脉管12均匀地散发非，依从应在每个受试者相同/相似的位置进行测量，以使实验组之间进行有意义的比较。 合规性和弹性模量之间的差别在于，弹性模量被归一化的材料的尺寸。因此，合规体现了结构刚度，而弹性模量裁判脉冲编码材料刚度。随着衰老，动脉壁的厚度的增加和弹性蛋白/胶原蛋白的比例降低，所以两者的结构刚度和材料刚性更大。 相比于合规性，PWV是动脉僵硬度的间接测量。 PWV是在哪一个压力脉冲行进沿着动脉的长度，并且由血管壁的性质的影响的速度。所述Moens-Korteweg等式用于PWV和弹性模量之间的关系进行建模：PWV 2 = E的h /（2ρR）其中E是增量弹性模量，h是壁厚，ρ是血液粘度，并且r是容器的半径。因此，一个更高的PWV值提出了一个更硬的容器。 合规性和弹性模量，可以对船只的切除部分实验体外测量。以确定是否符合，将容器段被安装在压力肌动描记13,14。容器内的压力增加逐步与日Ë产生变化直径使用视频显微镜跟踪。遵从压径数据确定。增量弹性系数可通过拉伸试验来测量。在这些实验中，将容器拉开分步进行和力 - 位移数据被收集，直到容器环断裂。应力和应变值可以被计算并绘制，以确定增量弹性模量。这些离体方法可用于评估的变化，影响刚度的被动特性。 在体内 ，除了墙壁内容，血管刚度由平滑肌张力和血压13,15,16动态影响。 PWV是最广泛使用的方法，用于测量在实验模型中体内主动脉刚度。 PWV可以使用无创多普勒超声或压平眼压计17来决定。压力脉冲的测量是在两个不同的位置和所需的时间遍历的距离的脉冲的脉波速度。因为PWV测量在主动脉的长度，它是刚性的平均值。大动脉是非线性弹性，所以刚度，因此PWV将随动脉压。因此，一个更高的PWV值可以从增加的僵硬或高压出现。 PWV值因此必须标准化为血压得出关于所述容器的刚性的结论。结合了血压与血管壁的被动性和血管活性介质的该改变色调会产生动脉僵硬的生理相关指数的影响的影响的测量方法。这种方法是通过测量PWV侵入使用的导管与在一个固定的距离13分开的两个压力传感器来实现。这种双重压力导管插入主动脉和血管活性药物，如苯福林或硝普钠，通过静脉内输注静脉导管，以提高和降低血压。 这个协议描述了一种方法，以确定从在小鼠模型中它的压力维关系体内主动脉刚度。这种方法有几个优点在侵入PWV测量。刚性指数，如合规性，可以从由该过程所收集的压力维数据来计算。此外，该技术允许对本地主动脉刚度测量，因为刚度是从单个位置测量。这种方法是在测量升主动脉刚度作为该区域的长度短使得PWV测量难以获得特别有用。存在的研究兴趣特别是在升主动脉，因为其机械性能影响冠脉循环的灌注和血管功能障碍的心脏反应。 以测量的主动脉体内的压径关系</e米&gt;，升主动脉被可视化和它的直径由超声成像测量。主动脉血压与一个压力导管侵入测量。血压是通过血管活性药物静脉输注增量改变。苯福林收缩血管，并用于提高主动脉的压力。硝普钠扩张血管和用于降低主动脉的压力。收缩压和舒张压主动脉直径及相应的主动脉压力测量每个压力增量。遵守可以从收集到的压径数据进行计算。

<table border="0" cellpadding="0" cellspacing="0" width="878">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Name of Material/ Equipment</td>
			<td style="width:197px;">Company</td>
			<td style="width:141px;">Catalog Number</td>
			<td style="width:239px;">Comments/Description</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Equipment</td>
			<td style="width:197px;"></td>
			<td style="width:141px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">High-resolution ultrasound machine</td>
			<td style="width:197px;">Visual Sonics</td>
			<td style="width:141px;">Vevo2100</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">13-24 MHz transducer</td>
			<td style="width:197px;">Visual Sonics</td>
			<td style="width:141px;">MS250</td>
			<td>Used for imaging rats</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">22-55 MHz transducer</td>
			<td style="width:197px;">Visual Sonics</td>
			<td style="width:141px;">MS550D</td>
			<td>Used for imaging mice</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Imaging Station</td>
			<td style="width:197px;">Visual Sonics</td>
			<td style="width:141px;">Imagine Station 1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;"></td>
			<td style="width:197px;"></td>
			<td style="width:141px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">1.2F Pressure catheter</td>
			<td style="width:197px;">Transonic</td>
			<td style="width:141px;">FTH-1211B-0018</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">SP200 pressure control unit</td>
			<td style="width:197px;">Transonic</td>
			<td style="width:141px;">FFS-095-DP01</td>
			<td></td>
		</tr>
		<tr height="52">
			<td height="52" style="height:52px;width:303px;">Standard Infusion Only Harvard Pump 11 Plus syringe pump</td>
			<td style="width:197px;">Harvard Apparatus</td>
			<td align="right" style="width:141px;">702208</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Isoflurane vaporizer</td>
			<td style="width:197px;">VetEquip</td>
			<td align="right" style="width:141px;">911103</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Induction chamber</td>
			<td style="width:197px;">VetEquip</td>
			<td align="right" style="width:141px;">941443</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">100% O2</td>
			<td style="width:197px;">Airgas</td>
			<td style="width:141px;">OX USP200</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:303px;">Single Stage Brass 0-50 psi General Purpose Cylinder Regulator CGA540</td>
			<td style="width:197px;">Airgas</td>
			<td style="width:141px;">Y11215B540</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Stereo Boom Stand Microscope</td>
			<td style="width:197px;">National Optical</td>
			<td style="width:141px;">420-BMSQ</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Fiber optic illuminator &#38; light pipe</td>
			<td style="width:197px;">Cole Palmer</td>
			<td style="width:141px;">EW-41500-50</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;"></td>
			<td style="width:197px;"></td>
			<td style="width:141px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Supplies</td>
			<td style="width:197px;"></td>
			<td style="width:141px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">30G x 1/2&#34; BD PrecisionGlide Needle</td>
			<td style="width:197px;">BD</td>
			<td align="right" style="width:141px;">305106</td>
			<td>For tail vein cannulation in mice</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Polyethylene Tubing PE10</td>
			<td style="width:197px;">Becton Dickinson</td>
			<td align="right" style="width:141px;">427401</td>
			<td>For tail vein cannulation in mice</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">27Gx1/2&#34; Surfloe winged infusion set</td>
			<td style="width:197px;">Terumo</td>
			<td style="width:141px;">SV*27EL</td>
			<td>For tail vein cannulation in rats</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;"></td>
			<td style="width:197px;"></td>
			<td style="width:141px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Signa Gel Electrode Gel</td>
			<td style="width:197px;">Parker</td>
			<td style="width:141px;">15-25</td>
			<td>Use for ECG recording</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Aquasonic Clear Ultrasound Gel</td>
			<td style="width:197px;">Parker</td>
			<td style="width:141px;">03-08</td>
			<td>Use for ultrasound</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;"></td>
			<td style="width:197px;"></td>
			<td style="width:141px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">1mL Sub-Q Syringes, 26G x 5/8&#34;</td>
			<td style="width:197px;">BD</td>
			<td align="right" style="width:141px;">309597</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Nair</td>
			<td style="width:197px;">Nair</td>
			<td style="width:141px;"></td>
			<td>Depilatory cream</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Histoacryl</td>
			<td style="width:197px;">TissueSeal</td>
			<td style="width:141px;">TS1050071FP</td>
			<td>Tissue glue</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Braided Silk Suture 6-0</td>
			<td style="width:197px;">Teleflex</td>
			<td style="width:141px;">104-S</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Dumostar P55 fine forceps</td>
			<td style="width:197px;">Roboz</td>
			<td style="width:141px;">RS-4984</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Microscissors</td>
			<td style="width:197px;">WPI</td>
			<td style="width:141px;">501839</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Fine scissors</td>
			<td style="width:197px;">FST</td>
			<td style="width:141px;">14060-11</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Medium forceps</td>
			<td style="width:197px;">Ted Pella</td>
			<td align="right" style="width:141px;">5665</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Hemostatic forceps</td>
			<td style="width:197px;">Roboz</td>
			<td style="width:141px;">RS-7131</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Non-sterile cotton gauze sponge</td>
			<td style="width:197px;">Fisherbrand</td>
			<td style="width:141px;">22-362-178</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Cotton tipped applicators</td>
			<td style="width:197px;">Oritan</td>
			<td style="width:141px;">803-WC</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Label tape</td>
			<td style="width:197px;">Fisherbrand</td>
			<td style="width:141px;">15-901-20</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;"></td>
			<td style="width:197px;"></td>
			<td style="width:141px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Drugs</td>
			<td style="width:197px;"></td>
			<td style="width:141px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Sodium chloride</td>
			<td style="width:197px;">Sigma Aldrich</td>
			<td style="width:141px;">S7653</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">R-Phenylephrine hydrochloride</td>
			<td style="width:197px;">Sigma Aldrich</td>
			<td style="width:141px;">P6126</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Sodium nitroprusside dihydrate</td>
			<td style="width:197px;">Sigma Aldrich</td>
			<td align="right" style="width:141px;">71778</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;"></td>
			<td style="width:197px;"></td>
			<td style="width:141px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Software</td>
			<td style="width:197px;"></td>
			<td style="width:141px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Prism</td>
			<td style="width:197px;">GraphPad</td>
			<td style="width:141px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Excel</td>
			<td style="width:197px;">Microsoft</td>
			<td style="width:141px;"></td>
			<td></td>
		</tr>
	</tbody>
</table>

measuring ascending aortic stiffness in vivo in mice using ultrasound

我们提出了一个协议，用于测量体内主动脉刚度利用高分辨率超声波成像的小鼠。主动脉直径由超声测量和主动脉血压与固态压力导管侵入测量。血压升高然后通过血管活性药物苯肾上腺素和硝普钠静滴增量降低。主动脉直径测量为每个压力步骤来表征升主动脉的压径的关系。从压径关系导出硬度指数可以从收集到的数据来计算。动脉顺应性的计算本协议描述。 这种技术可以用于研究底层与心血管疾病和衰老相关的增加的主动脉僵硬的机制。该技术生产的刚度相比体外的生理相关度量方法，因为pH值主动脉刚度ysiological影响在测量被并入。该技术的主要限制是在心动周期期间从主动脉的运动引入的测量误差。这种运动可以通过调整探针与主动脉运动的位置以及制备的主动脉压径关系的多个测量结果和扩大实验组大小进行补偿。

左心室和升主动脉的纵向图像心脏期间捕获在B模式，如图1中所示。可选择地，可以得到只在主动脉的纵向图像，如在图2中 。主动脉壁的运动周期出现在M型两条白线， 如图3，主动脉内腔中的行之间的区域。主动脉压力通过输注血管活性药物调制。 PE引起的主动脉压力， 如图4A所示 ，和SNP降低压力， 如图4B所示 。 M型记录时血压高原，输注开始后1分钟。主动脉压力逐渐改变通过改变施用的药物的剂量， 如图5。药物的剂量是通过输注的速率来控制。所有药物的剂量是在微克/公斤/分钟。最大和最小直径从吨测量他M模式， 如图3所示。这些直径对应于收缩压和记录由压力导管舒张主动脉的压力。 的3个心动周期的收缩和舒张的直径和压力值在基线和在各PE和SNP剂量被测量。在一种药物剂量的直径三次测量之间的标准偏差的范围为0.01mm至0.04毫米。主动脉直径可以绘制针对其相应的主动脉压来说明压径的关系， 如图6A所示 。 这些压径值被用来计算主动脉柔顺性。动脉顺应性的计算方法 C =（D SYS - ð 直径 ）/（P SYS - P 直径 ）（1） 其中D SYS和D 直径是收缩和舒张的直径和P sys和 P 直径是收缩压和舒张压。合规性和平均主动脉压（MAP），计算在基线和在各PE和SNP剂量。是否合格，对绘制地图展示的压力依赖性刚​​度。因为主动脉的非线性弹性的行为，符合增加的MAP，如在图6B中看到的降低。 <img alt="图1" src="/files/ftp_upload/52200/52200fig1highres.jpg" /> 图1：在B模式升主动脉纵向视图直径测量是从升主动脉离开左心室的纵向图像。 LV：左心室; PA：肺动脉; AA：升主动脉。肺动脉可视取决于探针放置。主动脉直径测量远端的主动脉瓣。用于捕捉这一形象探头的频率为40 MHz的。 图2：在B模式升主动脉的备选视图升主动脉的特征更加显着，并在左心室和心脏壁是不太明显。 AA：升主动脉; LV：左心室。探头用来记录这个形象频率为40 MHz的。 <img alt="图3" src="/files/ftp_upload/52200/52200fig3highres.jpg" /> 图3：主动脉上可视化的M型主动脉直径从M模式图像进行测定。主动脉壁的运动显示为两个波浪线。在两条线之间的空间是在主动脉管腔。的3个心动周期的收缩和舒张主动脉直径从M模式中测得。在该图像记录由压力导管，ECG信号和呼吸循环主动脉压力上的M模式显示为红色，绿色和黄色。探头FREQUENCŸ用来记录这个形象是40 MHz和采集扫描速度是1200赫兹。 <img alt="图4" src="/files/ftp_upload/52200/52200fig4highres.jpg" /> 图4：更改主动脉压力增量主动脉压力由药物的剂量输注增量改变。药物剂量是由输注速率调制。所有剂量均在微克/公斤/分钟。 <img alt="图5" src="/files/ftp_upload/52200/52200fig5highres.jpg" /> 图5：调制用血管活性药物的主动脉压力主动脉压力增加与输注血管收缩剂去氧肾上腺素（PE），并与输注血管扩张剂硝普钠（SNP）的下降。主动脉压高原1分钟的药物输注开始后。主动脉直径的M型被记录在平台期。（A）示出的上升主动脉压用360微克/公斤/分钟的PE输注。（B）中示出了与240微克/公斤/分钟的SNP输注主动脉压的下降。时的输注开始和M模式被记录的时间标记上的痕迹。 &#160;主动脉压力由药物的剂量输注增量改变。药物剂量是由输注速率调制。所有剂量均在微克/公斤/分钟。 <img alt="图6" src="/files/ftp_upload/52200/52200fig6highres.jpg" /> 图6：直径与压力和法规遵从与平均动脉压地块主动脉直径能抵挡它的相应的主动脉压，显示压力直径的关系（A）绘制。遵守可以计算每个压力递增和作图的平均主动脉压（MAP），以显示主动脉刚性（B）的压力依赖性。

Watch this Scientific Journal Video about Measuring Ascending Aortic Stiffness In Vivo in Mice Using Ultrasound at JoVE.com

Measuring Ascending Aortic Stiffness In Vivo in Mice Using Ultrasound

We describe a technique for measuring aortic stiffness from its pressure-diameter relationship in vivo in mice. Aortic diameter is recorded by ultrasound and aortic pressure is measured invasively with a solid-state pressure catheter. Blood pressure is changed incrementally and the resulting diameter is measured.

测量升主动脉刚度<em&gt;在体内</em&gt;小鼠使用超声

We present a protocol for measuring in vivo aortic stiffness in mice using high-resolution ultrasound imaging. Aortic diameter is measured by ultrasound ...

measuring-ascending-aortic-stiffness-in-vivo-in-mice-using-ultrasound

Research

JoVE Journal

Medicine

Measuring Ascending Aortic Stiffness In Vivo in Mice Using Ultrasound

15.9K 次观看.  Johns Hopkins University. We describe a technique for measuring aortic stiffness from its pressure-diameter relationship in vivo in mice. Aortic diameter is recorded by ultrasound and aortic pressure is measured invasively with a solid-state pressure catheter. Blood pressure is changed incrementally and the resulting diameter is measured.

视频: Measuring Ascending Aortic Stiffness In Vivo in Mice Using Ultrasound

Orthotopic Aortic Transplantation in Mice for the Study of Vascular Disease

Vascular procedures involving anastomoses in the mouse are generally thought to be difficult and highly dependent on the skill of the individual surgeon. This is largely true, but there are a number of important principles that can reduce the difficulty of these procedures and enhance reproducibility. Orthotopic aortic transplantation is an excellent procedure in which to learn these principles because it involves only two end-to-end anastomoses, but requires good suturing technique and handling of the vessels for consistent success. This procedure begins with the procurement of a length of abdominal aorta from a donor animal, followed by division of the native aorta in the recipient. The procured aorta is then placed between the divided ends of the recipient aorta and sutured into place using end-to-end anastomoses. To accomplish this objective successfully requires a high degree of concentration, good tools, a steady hand, and an appreciation of how easily the vasculature of a mouse can be damaged, resulting in thrombosis. Learning these important principles is what occupies most of the beginner's time when learning microsurgery in small rodents. Throughout this protocol, we refer to these important points. This model can be used to study vascular disease in a variety of different experimental systems1-8. In the context shown here, it is most often used for the study of post-transplant vascular disease, a common long-term complication of solid organ transplantation in which intimal hyperplasia occurs within the allograft. The primary advantage of the model is that it facilitates quantitative morphometric analyses and the transplanted vessel lies contiguous to the endogenous vessel, which can serve as an additional control9. The technique shown here is most often used for mice weighing 18-25 grams. We have accumulated most of our experience using the C57BL/6J, BALB/cJ, and C3H/HeJ strains.

We describe a technique in which a section of the abdominal aorta from a mouse is transplanted orthotopically to just below the renal arteries in an allogeneic or syngeneic recipient. This technique can be useful in studies in which transplantation of large arteries of uniform size is deemed advantageous.

原位主动脉瓣移植在小鼠血管疾病的研究

Vascular procedures involving anastomoses in the mouse are generally thought to be difficult and highly dependent on the skill of the individual surgeon. ...

科研

医学

In vivo 19F MRI for Cell Tracking

In vivo 19F MRI allows quantitative cell tracking without the use of ionizing radiation. It is a noninvasive technique that can be applied to humans. Here, we describe a general protocol for cell labeling, imaging, and image processing. The technique is applicable to various cell types and animal models, although here we focus on a typical mouse model for tracking murine immune cells. The most important issues for cell labeling are described, as these are relevant to all models. Similarly, key imaging parameters are listed, although the details will vary depending on the MRI system and the individual setup. Finally, we include an image processing protocol for quantification. Variations for this, and other parts of the protocol, are assessed in the Discussion section. Based on the detailed procedure described here, the user will need to adapt the protocol for each specific cell type, cell label, animal model, and imaging setup. Note that the protocol can also be adapted for human use, as long as clinical restrictions are met.

In vivo 19F MRI for Cell Tracking

We describe a general protocol for in vivo cell tracking using MRI in a mouse model with ex vivo labeled cells. A typical protocol for cell labeling, image acquisition processing and quantification is included.

在体内 19女性 MRI对细胞跟踪

In vivo 19F MRI allows quantitative cell tracking without the use of ionizing radiation. It is a noninvasive technique that can be applied to humans. ...

Ascending Aortic Constriction in Rats for Creation of Pressure Overload Cardiac Hypertrophy Model

Ascending aortic constriction is the most common and successful surgical model for creating pressure overload induced cardiac hypertrophy and heart failure. Here, we describe a detailed surgical procedure for creating pressure overload and cardiac hypertrophy in rats by constriction of the ascending aorta using a small metallic clip. After anesthesia, the trachea is intubated by inserting a cannula through a half way incision made between two cartilage rings of trachea. Then a skin incision is made at the level of the second intercostal space on the left chest wall and muscle layers are cleared to locate the ascending portion of aorta. The ascending aorta is constricted to 50&#8211;60% of its original diameter by application of a small sized titanium clip. Following aortic constriction, the second and third ribs are approximated with prolene sutures. The tracheal cannula is removed once spontaneous breathing was re-established. The animal is allowed to recover on the heating pad by gradually lowering anesthesia. The intensity of pressure overload created by constriction of the ascending aorta is determined by recording the pressure gradient using trans-thoracic two dimensional Doppler-echocardiography. Overall this protocol is useful to study the remodeling events and contractile properties of the heart during the gradual onset and progression from compensated cardiac hypertrophy to heart failure stage.

We describe a stepwise procedure for creating pressure overload and left ventricular hypertrophy in Wistar rats by constriction of the ascending aorta using a small metallic clip. This model is extensively used for studying remodeling changes during cardiac hypertrophy and for identifying and evaluating strategies for regression of such changes.

大鼠建立压力超负荷心肌肥厚模型在升主动脉缩窄

Ascending aortic constriction is the most common and successful surgical model for creating pressure overload induced cardiac hypertrophy and heart ...

Ultrasound-guided Transthoracic Intramyocardial Injection in Mice

Murine models of cardiovascular disease are important for investigating pathophysiological mechanisms and exploring potential regenerative therapies. Experiments involving myocardial injection are currently performed by direct surgical access through a thoracotomy. While convenient when performed at the time of another experimental manipulation such as coronary artery ligation, the need for an invasive procedure for intramyocardial delivery limits potential experimental designs. With ever improving ultrasound resolution and advanced noninvasive imaging modalities, it is now feasible to routinely perform ultrasound-guided, percutaneous intramyocardial injection. This modality efficiently and reliably delivers agents to a targeted region of myocardium. Advantages of this technique include the avoidance of surgical morbidity, the facility to target regions of myocardium selectively under ultrasound guidance, and the opportunity to deliver injectate to the myocardium at multiple, predetermined time intervals. With practiced technique, complications from intramyocardial injection are rare, and mice quickly return to normal activity on recovery from anesthetic. Following the steps outlined in this protocol, the operator with basic echocardiography experience can quickly become competent in this versatile, minimally invasive technique.

Echocardiography-guided percutaneous intramyocardial injection represents an efficient, reliable, and targetable modality for the delivery of gene transfer agents or cells into the murine heart. Following the steps outlined in this protocol, the operator can quickly become competent in this versatile, minimally invasive technique.

超声引导下经皮内注射小鼠

Murine models of cardiovascular disease are important for investigating pathophysiological mechanisms and exploring potential regenerative therapies. ...

Subcutaneous Angiotensin II Infusion using Osmotic Pumps Induces Aortic Aneurysms in Mice

Osmotic pumps continuously deliver compounds at a constant rate into small animals. This article introduces a standard protocol used to induce aortic aneurysms via subcutaneous infusion of angiotensin II (AngII) from implanted osmotic pumps. This protocol includes calculation of AngII amount and dissolution, osmotic pump filling, implantation of osmotic pumps subcutaneously, observation after pump implantation, and harvest of aortas to visualize aortic aneurysms in mice. Subcutaneous infusion of AngII through osmotic pumps following this protocol is a reliable and reproducible technique to induce both abdominal and thoracic aortic aneurysms in mice. Infusion durations range from a few days to several months based on the purpose of the study. AngII 1,000 ng/kg/min is sufficient to provide maximal effects on abdominal aortic aneurysmal formation in male hypercholesterolemic mouse models such as apolipoprotein E deficient or low-density lipoprotein receptor deficient mice. Incidence of abdominal aortic aneurysms induced by AngII infusion via osmotic pumps is 5 - 10 times lower in female hypercholesterolemic mice and also lower in both genders of normocholesterolemic mice. In contrast, AngII-induced thoracic aortic aneurysms in mice are not hypercholesterolemia or gender-dependent. Importantly, multiple features of this mouse model recapitulate those of human aortic aneurysms.

Subcutaneous implantation of osmotic pumps provides a convenient approach for prolonged and consistent delivery of compounds. This approach has been used extensively to study both abdominal and thoracic aortic aneurysms in mice.

使用渗透皮下血管紧张素Ⅱ输液泵诱导主动脉瘤小鼠

Osmotic pumps continuously deliver compounds at a constant rate into small animals.  This article introduces a standard protocol used to induce aortic ...

Depletion of Mouse Cells from Human Tumor Xenografts Significantly Improves Downstream Analysis of Target Cells

The use of in vitro cell line models for cancer research has been a useful tool. However, it has been shown that these models fail to reliably mimic patient tumors in different assays1. Human tumor xenografts represent the gold standard with respect to tumor biology, drug discovery, and metastasis research 2-4. Tumor xenografts can be derived from different types of material like tumor cell lines, tumor tissue from primary patient tumors4 or serially transplanted tumors. When propagated in vivo, xenografted tissue is infiltrated and vascularized by cells of mouse origin. Multiple factors such as the tumor entity, the origin of xenografted material, growth rate and region of transplantation influence the composition and the amount of mouse cells present in tumor xenografts. However, even when these factors are kept constant, the degree of mouse cell contamination is highly variable.
Contaminating mouse cells significantly impair downstream analyses of human tumor xenografts. As mouse fibroblasts show high plating efficacies and proliferation rates, they tend to overgrow cultures of human tumor cells, especially slowly proliferating subpopulations. Mouse cell derived DNA, mRNA, and protein components can bias downstream gene expression analysis, next-generation sequencing, as well as proteome analysis 5. To overcome these limitations, we have developed a fast and easy method to isolate untouched human tumor cells from xenografted tumor tissue. This procedure is based on the comprehensive depletion of cells of mouse origin by combining automated tissue dissociation with the benchtop tissue dissociator and magnetic cell sorting. Here, we demonstrate that human target cells can be can be obtained with purities higher than 96% within less than 20 min independent of the tumor type.

Human tumor xenografts are vascularized and infiltrated by cells of mouse origin during the growth phase in vivo. To circumvent the bias caused by these contaminating cells during downstream analysis, we developed a method allowing for comprehensive depletion of all mouse cells by magnetic cell sorting.

从人类肿瘤异种移植的小鼠细胞的消耗显着改善靶细胞下游分析

The use of in vitro cell line models for cancer research has been a useful tool. However, it has been shown that these models fail to reliably mimic ...

Ultrasound-based Pulse Wave Velocity Evaluation in Mice

Arterial stiffness can be evaluated by calculating pulse wave velocity (PWV), i.e., the speed with which the pulse wave travels in a conduit vessel. This parameter is being increasingly investigated in small rodent models in which it is used for assessing alterations in vascular function related to particular genotypes/treatments or for characterizing cardiovascular disease progression. This protocol describes an image processing algorithm which leads to non-invasive arterial PWV measurement in mice using ultrasound (US) images only. The proposed technique has been used to assess abdominal aorta PWV in mice and evaluate its age-associated changes.
Abdominal aorta US scans are obtained from mice under gaseous anesthesia using a specific US device equipped with high-frequency US probes. B-mode and Pulse-Wave Doppler (PW-Doppler) images are analyzed in order to obtain diameter and mean velocity instantaneous values, respectively. For this purpose, edge detection and contour tracking techniques are employed. The single-beat mean diameter and velocity waveforms are time aligned and combined in order to achieve the diameter-velocity (lnD-V) loop. PWV values are obtained from the slope of the linear part of the loop, which corresponds to the early systolic phase.
With the present approach, anatomical and functional information about the mouse abdominal aorta can be non-invasively achieved. Requiring the processing of US images only, it may represent a useful tool for the non-invasive characterization of different arterial sites in the mouse in terms of elastic properties. The application of the present technique can be easily extended to other vascular districts, such as the carotid artery, thus providing the possibility to obtain a multi-site arterial stiffness assessment.

Arterial stiffness represents a key factor in cardiovascular disease and pulse wave velocity (PWV) can be considered as a surrogate index for arterial stiffness. This protocol describes an image processing algorithm for calculating PWV in mice based on ultrasound image processing that is applicable at different arterial sites.

基于超声脉搏波速度评价小鼠

Arterial stiffness can be evaluated by calculating pulse wave velocity (PWV), i.e., the speed with which the pulse wave travels in a conduit vessel. This ...

Minimally Invasive Transverse Aortic Constriction in Mice

Minimally invasive transverse aortic constriction (MTAC) is a more desirable method for the constriction of the transverse aorta in mice than standard open-chest transverse aortic constriction (TAC). Although transverse aortic constriction is a highly functional method for the induction of high pressure in the left ventricle, it is a more difficult and lengthy procedure due to its use of artificial ventilation with tracheal intubation. TAC is oftentimes also less survivable, as the newer method, MTAC, neither requires the cutting of the ribs and intercostal muscles nor tracheal intubation with a ventilation setup. In MTAC, as opposed to a thoracotomy to access to the chest cavity, the aortic arch is reached through a midline incision in the anterior neck. The thyroid is pulled back to reveal the sternal notch. The sternum is subsequently cut down to the second rib level, and the aortic arch is reached simply by separating the connective tissues and thymus. From there, a suture can be wrapped around the arch and tied with a spacer, and then the sternal cut and skin can be closed. MTAC is a much faster and less invasive way to induce left ventricular hypertension and enables the possibility for high-throughput studies. The success of the constriction can be verified using high-frequency trans-thoracic echocardiography, particularly color Doppler and pulsed-wave Doppler, to determine the flow velocities of the aortic arch and left and right carotid arteries, the dimension of the blood vessels, and the left ventricular function and morphology. A successful constriction will also trigger significant histopathological changes, such as cardiac muscle cell hypertrophy with interstitial and perivascular fibrosis. Here, the procedure of MTAC is described, demonstrating how the resulting flow changes in the carotid arteries can be examined with echocardiography, gross morphology, and histopathological changes in the heart.

Minimally invasive transverse aortic constriction (MTAC) conserves the essentials of regular transverse aortic constriction (TAC) while eliminating the use of a ventilator with tracheal intubation. It proves to be a highly desirable method for high-throughput studies on left ventricular overload, particularly in translational studies.

微创横向主动脉缩窄小鼠

Minimally invasive transverse aortic constriction (MTAC) is a more desirable method for the constriction of the transverse aorta in mice than standard ...

A Closed-chest Model to Induce Transverse Aortic Constriction in Mice

Research on cardiac hypertrophy and heart failure is frequently based on pressure overload mouse models induced by TAC. The standard procedure is to perform a partial thoracotomy to visualize the transverse aortic arch. However, the surgical trauma caused by the thoracotomy in open-chest models changes the respiratory physiology as the ribs are dissected and left unattached after chest closure. To prevent this, we established a minimally invasive, closed chest approach via lateral thoracotomy. Herein we approach the aortic arch via the 2nd intercostal space without entering the chest cavities, leaving the mouse with a less traumatic injury to recover from. We perform this operation using standard laboratory settings for open chest TAC procedures with equal survival rates. Apart from maintaining physiological breathing patterns due to the closed chest approach, the mice seem to benefit by showing rapid recovery, as the less invasive technique appears to facilitate a fast healing process and to reduce immune response after trauma.

Here, we present a protocol of Transverse Aortic constriction (TAC) via a lateral thoracotomy. This technique is a minimally invasive, closed chest surgical procedure aiming to simulate pressure overload and heart failure in mice utilizing standard TAC laboratory settings.

诱导小鼠横向主动脉狭窄的闭合胸模型

Research on cardiac hypertrophy and heart failure is frequently based on pressure overload mouse models induced by TAC. The standard procedure is to ...

Using a Chemical Biopsy for Graft Quality Assessment

Kidney transplantation is a life-saving treatment for a large number of people with end-stage renal dysfunction worldwide. The procedure is associated with an increased survival rate and greater quality of patient&#8217;s life when compared to conventional dialysis. Regrettably, transplantology suffers from a lack of reliable methods for organ quality assessment. Standard diagnostic techniques are limited to macroscopic appearance inspection or invasive tissue biopsy, which do not provide comprehensive information about the graft. The proposed protocol aims to introduce solid phase microextraction (SPME) as an ideal analytical method for comprehensive metabolomics and lipidomic analysis of all low molecular compounds present in kidneys allocated for transplantation. The small size of the SPME probe enables performance of a chemical biopsy, which enables extraction of metabolites directly from the organ without any tissue collection. The minimum invasiveness of the method permits execution of multiple analyses over time: directly after organ harvesting, during its preservation, and immediately after revascularization at the recipient&#8217;s body. It is hypothesized that the combination of this novel sampling method with a high-resolution mass spectrometer will allow for discrimination of a set of characteristic compounds that could serve as biological markers of graft quality and indicators of possible development of organ dysfunction.

The protocol presents utilization of the chemical biopsy approach followed by comprehensive metabolomic and lipidomic analysis for quality assessment of kidney grafts allocated for transplantation.

使用化学活检进行移植质量评估

Kidney transplantation is a life-saving treatment for a large number of people with end-stage renal dysfunction worldwide. The procedure is associated ...