Name: arterial pouch microsurgical bifurcation aneurysm model in the rabbit
Uploaded: 2020-05-14T13:00:00.000+00:00
Duration: 6 min 11 s
Description: Watch this Scientific Journal Video about Arterial Pouch Microsurgical Bifurcation Aneurysm Model in the Rabbit at JoVE.com

作者感谢Olgica Beslac和Kay Nettelbeck在围手术期的出色支持和技术援助，以及Alessandra Bergadano，DVM，PhD，PhD对长期动物健康的专门监督。

所有兽医护理均按照机构指南进行（所有实验均由瑞士伯尔尼州动物护理地方委员会批准（BE 108/16）），并在董事会认证的兽医麻醉师的监督下进行。17，18严格遵守了ARR指南和3R原则。
注意:将所有动物饲养在 22\u201224 摄氏度 （°C） 的室温下，并保持 12 小时 （h） 的亮/暗循环。每次都提供免费的水，颗粒和随意的干草饮食。使用非参数Wilcoxon-Mann-Whitney-U检验进行统计分析。概率值 （p） ≤ 0.05 被认为是显著的。
1. 术前阶段
<ol><li>对所有计划手术的兔子进行详细的术前临床检查，紧挨着一个安静的无菌手术室，保持23±3°C的温度。<ol>
<li>记录每只动物的体重，宏观评估粘膜，毛细血管再填充时间和脉冲质量。</li>
		<li>进一步用听诊器和腹部触诊进行心脏听诊。</li>
		<li>根据临床发现，将美国麻醉师协会（ASA）分类归因于每只兔子19。在研究中仅包括ASA I评分的动物。</li>
		<li>用电动剃须刀剃除双耳外耳，并在耳动脉和静脉上涂抹丙胺卡因 - 利多卡因乳膏。</li>
	</ol>
</li>
	<li>用20毫克（mg）/killogram（kg）氯胺酮，100mg / kg右美托咪定和0.3mg / kg美沙酮的组合通过注射器镇静兔子皮下注射（SC）。</li>
	<li>让每只动物不受干扰至少15分钟。</li>
	<li>此后，通过松开的面罩用3升（l）/分钟（分钟）补充氧合，并通过脉搏血氧仪进行稳定监测，将一个22 G插管放在左耳中央动脉，另一个22G套管放在对侧耳的耳静脉中。</li>
	<li>剃除手术区域（颈部），皮内注射0.75%围切期罗哌卡因。接下来剃掉前额，准备放置小儿脑电图（EEG）传感器。</li>
	<li>用丙泊酚1-2mg / kg静脉注射（IV）诱导全身麻醉以起作用。然后在二氧化碳图控制下立即用硅胶管（内径3毫米（mm））插管所有兔子的气管。之后，将所有兔子运送到手术室，将它们放在背卧位，并将管子连接到儿科圆圈系统。</li>
	<li>通过氧气中的异氟醚实现麻醉加深和维持，目标是最大潮气末异氟醚浓度为1.3%。</li>
	<li>确保临床和仪器监测（脉搏血氧仪，多普勒和侵入性血压，3导联心电图，脑电图，直肠温度监测以及吸入和呼出的气体），直到气管拔管。</li>
	<li>为了保持水合作用，通过静脉通路以5ml / kg / h的连续速率输注（CRI）提供Ringer的乳酸盐。始终以10分钟的间隔使用脚趾捏合来确认适当的麻醉。</li>
	<li>使用聚维酮碘从胸骨厩到两个颌角对手术区域进行消毒。现在，对手术场进行无菌覆盖。</li>
	<li>在手术过程中，使用 CRI 为 50 μg/kg/min 的利多卡因和 3\u201210 μg/kg/min 的芬太尼镇痛。应用自发性或辅助通气以及允许性高碳酸血症。在手术期间至少进行一次动脉血气分析。</li>
	<li>用去甲肾上腺素治疗相关低血压（平均动脉压< 60 mmHg）。使用加热垫或加热强制空气加热系统防止体温过低（直肠温度≤38°C）。</li>
</ol>2. 手术阶段 – 步骤 I
<ol><li>从胸骨厩到颌角/喉部水平的正中皮肤切口开始手术。用手术刀，手术剪刀和镊子彻底切开皮肤和软组织。通过钝性夹层将皮下和脂肪垫内侧分开。</li>
	<li>使用微镊子和手术剪刀，通过钝性夹层进入左侧胸锁乳突肌的前上脊。</li>
	<li>在宏观上，进行钝器准备，并小心地将左CCA与远端的迷走神经分开，以进一步使用微镊子和手术剪刀避免喉部麻痹（图2）。请注意，左CCA的分叉是术中的标志（图3 和 图4A）。对于以下所有步骤，请使用软组织扩张器来改善手术可视化。</li>
	<li>在成功制备并从迷走神经中解放左远端CCA后，局部给予罂粟碱（40mg / ml，1:1稀释在0.9%等渗氯化钠溶液中）。用微拭子持续保护所有血管段，然后进一步从外部给予罂粟碱。将浸泡过罂粟碱的左CCA置于自体肌肉组织下方，以保护血管在手术显微镜的光线下干燥。</li>
	<li>在手术过程中切换侧面，同时最大限度地提高外科医生的舒适度。在右侧重复相同的外科手术。在远端和近端切开CCA直至预定义的标志点（颌角/喉部和颈内静脉水平的颈动脉分叉; 图4A，B）。如前所述，重新插入吊具并施用微拭子和罂粟碱。</li>
	<li>在右近端CCA结扎之前，通过静脉耳导管全身注射肝素（500国际单位（IU）/kg）。</li>
	<li>从现在开始使用手术显微镜。首先，直接在宏观可见的近端标志点末端用4-0不可吸收缝合线连接右近端CCA，以避免动脉血管上的任何张力。<ol>
<li>其次，通过使用血管夹进行测量，将6-0不可吸收的结扎正好在4\u20125 mm的远端应用，考虑到从第一个4-0结扎的远端切割后，所得动脉袋在每只动物中的标准化长度约为3\u20124 mm（图5A，C）。</li>
	</ol>
</li>
	<li>拧紧6-0结扎后，用临时血管夹（通常用于脑动脉瘤手术）将右CCA尽可能远地夹住，以避免任何内皮损伤并形成用于冲洗的长血管段，以防止血栓形成（图5B）。</li>
	<li>现在在4-0不可吸收结扎的远端进行切割。为了收获动脉袋（图5C），在6-0不可吸收结扎的远端进行第二次切割。</li>
	<li>从所有软组织中仔细清洁动脉袋，并用血管夹测量其长度，宽度和深度（图5C）。如果不需要进一步修饰，请将自体动脉移植物保存在肝素化溶液（500 IU / 100ml在0.9%等渗氯化钠中）中，直到进一步使用。</li>
</ol>3. 动脉袋退化
<ol><li>如果需要动脉袋降解，请仔细清洁软组织，并在实验当天用100IU的猪弹性蛋白酶在室温下溶解在5ml Tris缓冲液中预腮管20分钟。不要使用刷子技术。使用振荡器将动脉袋在光内和光外孵育。</li>
	<li>在将袋子放入0.9%等渗氯化钠的肝素化溶液中之前，用解剖镊子在0.9%等渗氯化钠溶液中轻轻滑动三次3分钟，以洗出剩余的猪弹性蛋白酶。</li>
	<li>如果需要，用硅胶制成的微管保持动脉袋的管腔打开;在整个手术过程中用湿微衬垫精心保护左右CCA。</li>
</ol>4. 手术阶段 – 第二步
<ol><li>为了进一步准备CCA，将两个圆形的微拭子直接放在其下方，以更浅地移动动脉。现在，在远端第三端的左CCA下方放置一个带有紫色衬垫的微拭子，以便更好地可视化动脉。</li>
	<li>用0.9%等渗氯化钠与溶解在100ml 0.9%等渗氯化钠中的500IU肝素溶液冲洗右近端CCA。为了形成无张力的吻合口，使用手术剪刀将其隧道输送到左侧，将正确的CCA放在脂肪垫/腹膜肌肉组织下方。切除动脉的软组织。<ol>
<li>现在使用微型剪刀和镊子在右侧CCA的近端进行2毫米鱼嘴切口。</li>
	</ol></li>
	<li>更换手术台上的一侧。用另一个临时血管夹夹夹住左远端CCA，然后用两个临时血管夹左端CCA。使用湿微签保护所有暴露的血管段，防止在手术光下干燥。</li>
	<li>将左CCA的远端三分之一完全从软组织中解放出来并进行动脉切开术。使用手术微镊子，轻轻抓住一些软组织。现在抬高动脉，用手术微剪刀缓慢切开左远端CCA。用肝素冲洗血管段（500IU溶解在100ml 0.9%等渗氯化钠溶液中）。</li>
	<li>用弯曲的微镊子和微剪刀进行动脉切开术后，将位于左CCA远端三分之一远端的动脉切开术扩大，测量颈动脉右钝和自体移植物直径的约2倍。这允许足够的血液流入动脉袋。</li>
	<li>将动脉袋从肝素盐水溶液中取出。将袋子放在手术场中，在那里计划分叉。开始用不可吸收的9-0缝合线缝合右颈动脉钝口的后部，然后在鱼嘴切口水平处的颅骨后侧缝合。通过单针完成从远端到近端的缝合。</li>
	<li>缝合时，通过连续灌溉保持所有弹性蛋白酶预浸渍袋湿润。在缝合袋的血管壁时，使用弯曲的手术微镊子轻轻打开管腔及其尖端。每当缝合左或右近端CCA的部分时，使用直式手术微镊子。之后，缝合水平背面。</li>
	<li>接下来缝合水平前侧，从动脉瘤的圆顶开始移动到其底部。之后，从正面远端的单针开始，尾部移动。<ol>
<li>对于缝合吻合口的所有步骤 4.5\u20124.8，请注意抓住靠近动脉切开术的血管部分，以避免医源性狭窄。此外，在整个外科手术过程中，用装有肝素化氯化钠溶液（500 IU溶解在100ml 0.9%等渗氯化钠中）的注射器在光下连续润湿所有血管段，并用湿微签保护它们。</li>
		<li>在完成吻合口之前，用肝素化的0.9%等渗氯化钠溶液在腔内（500IU溶解在100ml 0.9%等渗氯化钠中）冲洗整个复合物。请注意，弹性蛋白酶修饰的动脉袋必须尽快缝制，因为它们有强烈的干燥和血栓形成倾向。由于袋中残余弹性蛋白酶浓度对消化周向血管的侵袭性行为，因此请快速进行手术以快速重新灌注血管复合物。</li>
	</ol></li>
	<li>逐步移除所有临时血管钳。<ol>
<li>从左侧CCA上取下远端夹钳。接受轻微出血，并通过在吻合口上轻轻印刻微拭子来固定出血。然后，取下右侧CCA的夹子，用微拭子和镊子轻轻按压，以避免血栓形成。</li>
		<li>如果需要，更换临时血管夹以提供足够的凝血。之后，从左侧近端卸下两个血管夹。如果在任何步骤中需要，请更换夹子以允许凝固或进行重新拼接。</li>
	</ol></li>
	<li>在该阶段进行血管复合物的荧光血管造影（图6 和 图7）。 注意:荧光血管造影是通过施用1ml荧光素IV，使用2个带通滤光片，带摄像机的智能手机和自行车聚光灯进行的。这一程序已在别处20，21，22中描述。</li>
	<li>最后，关闭手术地点。用3-0可吸收的缝合线重新填充并轻轻缝合脂肪垫，单个节点以保护吻合口。以相同的方式关闭皮下和皮肤。</li>
</ol>5. 术后阶段
<ol><li>在手术结束时停止异氟醚和全身镇痛，并在吞咽反射恢复后立即提供气管拔管。</li>
	<li>静脉注射0.5毫克/千克美洛昔康，静脉注射10毫克/千克阿司匹林（ASS），100微克维生素B12 SC和20毫克/千克氯氧基静脉注射。</li>
	<li>提供补充性氧合和积极升温，直到兔子自发恢复胸骨卧位。</li>
	<li>根据啮齿动物和兔子疼痛评估和管理指南23，24，在前三天每天进行四次术后随访和动物护理。</li>
	<li>根据疼痛评估评分表，通过外耳上施用芬太尼贴剂（12μg/ h），美洛昔康每天一次SC持续三天，美沙酮作为抢救治疗SC进行术后镇痛。在所有兔子中皮下注射250 IU / kg低分子肝素（LMH）三天。</li>
</ol>

这项工作得到了瑞士阿劳Kantonsspital Aarau研究委员会和瑞士国家科学基金会SNF（310030_182450）的研究基金的支持。作者对所提交研究的设计和进行负全部责任，并声明没有竞争利益。

我们的研究证明了在兔子中建立具有不同壁条件的真正分叉动脉瘤模型的可行性。总体而言，该研究纳入了14只平均体重为3.7±0.09 kg，平均年龄为112±3天的新西兰大白兔。85.72%的动脉瘤在28天的随访期间保持专利。两只动物过早死亡（死亡率为12.5%）。
先前的研究建议使用多种颅外动脉瘤模型来分析血管内动脉瘤治疗的管理25，26...

颅内动脉瘤 （IA） 破裂引起的蛛网膜下腔出血可通过血管内或显微外科闭塞技术有效控制1，2，3，4。不同的血管内疗法，克服盘绕后IA复发的主要局限性，在过去几十年中变得越来越重要，导致对测试血管内装置的需求增加。为了测试这些新的治疗方法，高度需要尊重流变学特性，血流动力学和动脉瘤壁条件的适当动物模型5，6，7。在这种情况下，临床和临床前研究已经揭示了动脉瘤壁疾病对动脉瘤破裂和闭塞后复发的重要作用，特别关注壁细胞的丧失7，8，9。
到目前为止，兔子的实验性动脉瘤通常是通过弹性蛋白酶孵育的颈总动脉（CCA）残端或缝合成人工CCA分叉的静脉袋产生的。10，11，12，13，14，15，16 因此，从未描述过真正的动脉袋分叉模型。
本研究的目的是设计一种安全，快速和标准化的技术，用于在兔子模型中创建具有不同壁条件的分叉动脉瘤的显微外科手术（图1）。这是通过将未修饰和修饰的动脉袋缝合到两个CCA的人工分叉中来实现的。

<table><tbody><tr><td>3-0 resorbable suture</td><td>Ethicon Inc., USA</td><td>VCP428G</td><td></td></tr><tr><td>4-0 non-absorbable suture</td><td>B. Braun, Germany</td><td>G0762563</td><td></td></tr><tr><td>6-0 non-absorbable suture</td><td>B. Braun, Germany</td><td>C0766070</td><td></td></tr><tr><td>9-0 non-absorbable suture</td><td>B. Braun, Germany</td><td>G1111140</td><td></td></tr><tr><td>Adrenaline</td><td>Amino AG</td><td>1445419</td><td>any generic</td></tr><tr><td>Amiodarone</td><td>Helvepharm AG</td><td>5078567</td><td>any generic</td></tr><tr><td>Anesthesia machine</td><td>Dr&amp;auml;ger</td><td></td><td>any other</td></tr><tr><td>Aspirin</td><td>Sanofi-Aventis (Suisse) SA</td><td>622693</td><td>any generic</td></tr><tr><td>Atropine</td><td>Labatec Pharma SA</td><td>6577083</td><td>any generic</td></tr><tr><td>Bandpass filter blue</td><td>Thorlabs</td><td>FD1B</td><td>any other</td></tr><tr><td>Bandpass filter green</td><td>Thorlabs</td><td>FGV9</td><td>any other</td></tr><tr><td>Bipolar forceps</td><td></td><td></td><td>any other</td></tr><tr><td>Bicycle spotlight</td><td></td><td></td><td>any other</td></tr><tr><td>Biemer vessel clip (2 x)</td><td>B. Braun Medical AG, Aesculap, Switzerland</td><td>FD560R</td><td>temporary</td></tr><tr><td>Bispectral index (neonatal)</td><td></td><td></td><td>any other</td></tr><tr><td>Blood pressure cuff (neonatal)</td><td></td><td></td><td>any other</td></tr><tr><td>Clamoxyl</td><td>GlaxoSmithKline AG</td><td>758808</td><td>any generic</td></tr><tr><td>Dexmedetomidine</td><td>Ever Pharma</td><td>136740-1</td><td>any generic</td></tr><tr><td>Electrocardiogram electrodes</td><td></td><td></td><td>any other</td></tr><tr><td>Elastase</td><td>Sigma Aldrich</td><td>45125</td><td>any generic</td></tr><tr><td>Ephedrine</td><td>Amino AG</td><td>1435734</td><td>any generic</td></tr><tr><td>Esmolol</td><td>OrPha Swiss GmbH</td><td>3284044</td><td>any generic</td></tr><tr><td>Fentanyl (intravenous use)</td><td>Janssen-Cilag AG</td><td>98683</td><td>any generic</td></tr><tr><td>Fentanyl (transdermal)</td><td>Mepha Pharma AG</td><td>4008286</td><td>any generic</td></tr><tr><td>Fluoresceine</td><td>Curatis AG</td><td>5030376</td><td>any generic</td></tr><tr><td>Fragmin</td><td>Pfizer PFE Switzerland GmbH</td><td>1906725</td><td>any generic</td></tr><tr><td>Glyco</td><td></td><td></td><td>any generic</td></tr><tr><td>Heating pad</td><td></td><td></td><td>any other</td></tr><tr><td>Isotonic sodium chloride solution (0.9%)</td><td>Fresenius KABI</td><td>336769</td><td>any generic</td></tr><tr><td>Ketamine</td><td>Pfizer</td><td>342261</td><td>any generic</td></tr><tr><td>Laboratory shaker</td><td>Stuart</td><td>SRT6</td><td>any other</td></tr><tr><td>Lidocaine</td><td>Streuli Pharma AG</td><td>747466</td><td>any generic</td></tr><tr><td>Longuettes</td><td></td><td></td><td>any other</td></tr><tr><td>Metacam</td><td>Boehringer Ingelheim</td><td>P7626406</td><td>any generic</td></tr><tr><td>Methadone</td><td>Streuli Pharma AG</td><td>1084546</td><td>any generic</td></tr><tr><td>Microtubes</td><td></td><td></td><td>any other</td></tr><tr><td>Micro needle holder</td><td></td><td></td><td>any other</td></tr><tr><td>Midazolam</td><td>Accord Healthcare AG</td><td>7752484</td><td>any generic</td></tr><tr><td>Needle holder</td><td></td><td></td><td>any other</td></tr><tr><td>O2-Face mask</td><td></td><td></td><td>any other</td></tr><tr><td>Operation microscope</td><td>Wild Heerbrugg</td><td></td><td>any other</td></tr><tr><td>Papaverine</td><td>Bichsel</td><td></td><td>any generic</td></tr><tr><td>Prilocaine-lidocaine creme</td><td>Emla</td><td></td><td>any generic</td></tr><tr><td>Propofol</td><td>B. Braun Medical AG, Switzerland</td><td></td><td>any generic</td></tr><tr><td>Pulse oxymeter</td><td></td><td></td><td>any generic</td></tr><tr><td>Rectal temperature probe (neonatal)</td><td></td><td></td><td>any other</td></tr><tr><td>Ropivacaine</td><td>Aspen Pharma Schweiz GmbH</td><td>1882249</td><td>any generic</td></tr><tr><td>Scalpell</td><td>Swann-Morton</td><td>210</td><td>any other</td></tr><tr><td>Small animal shaver</td><td></td><td></td><td>any other</td></tr><tr><td>Smartphone</td><td></td><td></td><td>any other</td></tr><tr><td>Soft tissue forceps</td><td></td><td></td><td>any other</td></tr><tr><td>Soft tissue spreader</td><td></td><td></td><td>any other</td></tr><tr><td>Stainless steel sponge bowls</td><td></td><td></td><td>any other</td></tr><tr><td>Sterile micro swabs</td><td></td><td></td><td>any other</td></tr><tr><td>Stethoscope</td><td></td><td></td><td>any other</td></tr><tr><td>Straight and curved micro-forceps</td><td></td><td></td><td>any other</td></tr><tr><td>Straight and curved micro-scissors</td><td></td><td></td><td>any other</td></tr><tr><td>Straight and curved forceps</td><td></td><td></td><td>any other</td></tr><tr><td>Surgery drape</td><td></td><td></td><td>any other</td></tr><tr><td>Surgical scissors</td><td></td><td></td><td>any other</td></tr><tr><td>Syringes 1 ml, 2ml and 5 ml</td><td></td><td></td><td>any other</td></tr><tr><td>Tris-Buffer</td><td>Sigma Aldrich</td><td>93302</td><td>any generic</td></tr><tr><td>Vascular clip applicator</td><td>B. Braun, Germany</td><td>FT495T</td><td></td></tr><tr><td>Vein and arterial catheter 22 G</td><td></td><td></td><td>any generic</td></tr><tr><td>Vitarubin</td><td>Streuli Pharma AG</td><td>6847559</td><td>any generic</td></tr><tr><td>Yasargil titan standard clip (2 x)</td><td>B. Braun Medical AG, Aesculap, Switzerland</td><td>FT242T</td><td>temporary</td></tr></tbody></table>

arterial pouch microsurgical bifurcation aneurysm model in the rabbit

颅内动脉瘤的血管内治疗在过去几十年中变得越来越重要，因此对测试血管内装置的需求增加。高度有必要使用符合流变学、血流动力学和动脉瘤壁条件的动物模型。因此，本研究的目的是设计一种新的标准化和可重复的手术技术，以在兔子中产生具有未修饰和修饰壁条件的自体动脉袋分叉动脉瘤。
分叉动脉瘤是通过左颈总动脉右侧吻合术产生的，两者都是显微外科缝合的动脉袋的母动脉。从右颈总动脉近端取出移植物，用于对照组（n = 7，立即自体再植入）或修饰组（n = 7，与100个国际单位弹性蛋白酶一起孵育20分钟，自体再植入）组。创建后立即通过荧光血管造影控制袋和母动脉通畅性。在随访（28天）时，所有兔子都接受了造影剂增强磁共振血管造影和荧光血管造影，然后进行动脉瘤收获，宏观和组织学评估。
共有16只雌性新西兰白兔作。两只动物过早死亡。在随访时，85.72%的动脉瘤仍然是专利。两组都显示动脉瘤大小随着时间的推移而增加;对照组（创建时为6.48±1.81 mm3 ，随访时为19.85±6.40 mm3 ，p = 0.037），这比修饰组（创建时为8.03±1.08 mm3 ，随访时为20.29±6.16 mm3 ）更为明显，p = 0.054）。
我们的研究结果表明，这种新的兔子模型是充分的，它允许在显微外科方法中创建具有不同壁条件的分叉动脉瘤。鉴于良好的长期通畅性和动脉瘤随时间推移生长的特性，该模型可作为新型血管内疗法临床前评估的重要工具。

在由七只动物组成的试点系列之后，共有16只动物被纳入实验方案。两只动物过早死亡，因此被排除在最终分析之外（死亡率为12.5%）。在14只动物身上计算，对照组和修饰组在荧光血管造影过程中的即时动脉瘤通畅率为71.43%。四个动脉瘤必须通过连续的血栓清宫重新打开，并且在重复荧光血管造影后，所有病例都有记录的通畅性（100%）。MR和荧光血管造影组的动脉瘤通畅率为85.72%，28天后随访时?...

Watch this Scientific Journal Video about Arterial Pouch Microsurgical Bifurcation Aneurysm Model in the Rabbit at JoVE.com

Arterial Pouch Microsurgical Bifurcation Aneurysm Model in the Rabbit

开发和测试用于颅内动脉瘤治疗的血管内装置仍然非常重要。今天使用的大多数动脉瘤模型都忽略了动脉退行性壁的重要特征或真正分叉的血液动力学。因此，我们设计了一种新型的兔动脉袋分岔模型。

兔动脉袋显微外科分叉动脉瘤模型

Endovascular treatment for intracranial aneurysms gained importance over the past decades, consequently there is an increased need of testing endovascular ...

arterial-pouch-microsurgical-bifurcation-aneurysm-model-in-the-rabbit

Research

JoVE Journal

Neuroscience

2.3K 次观看.  Kantonsspital Aarau. 开发和测试用于颅内动脉瘤治疗的血管内装置仍然非常重要。今天使用的大多数动脉瘤模型都忽略了动脉退行性壁的重要特征或真正分叉的血液动力学。因此，我们设计了一种新型的兔动脉袋分岔模型。

视频: Arterial Pouch Microsurgical Bifurcation Aneurysm Model in the Rabbit

Microsurgical Venous Pouch Arterial-Bifurcation Aneurysms in the Rabbit Model: Technical Aspects

For ruptured human cerebral aneurysms endovascular embolization has become an equivalent alternative to aneurysm clipping.1 However, large clinical trials have shown disappointing long-term results with unacceptable high rates of aneurysm recanalization and delayed aneurysm rupture.2 To overcome these problems, animal experimental studies are crucial for the development of better endovascular devices.3-5
Several animal models in rats, rabbits, canines and swine are available.6-8 Comparisons of the different animal models showed the superiority of the rabbit model with regard to hemodynamics and comparability of the coagulation system and cost-effectiveness.9-11 
The venous pouch arterial bifurcation model in rabbits is formed by a venous pouch sutured into an artificially created true bifurcation of both common carotid arteries (CCA). The main advantage of this model are true bifurcational hemodynamics.12 The major drawbacks are the sofar high microsurgical technical demands and high morbidity and mortality rates of up to 50%.13 These limitations have resulted in less frequent use of this aneurysm model in the recent years. These shortcomings could be overcome with improved surgical procedures and modified peri- and postoperative analgetic management and anticoagulation.14-16 Our techniques reported in this paper demonstrate this optimized technique for microsurgical creation of arterial bifurcation aneurysms.

An optimized technique for the microsurgical creation of arterial bifurcation aneurysms mimicking bifurcation human cerebral aneurysms is described. A venous pouch is sutured into an artificially created true bifurcation of both common carotid arteries. Facilitated microsurgical techniques and aggressive postoperative anticoagulation and analgesia lead to minimized morbidity rates and high aneurysm patency rates.

显微静脉袋分岔动脉瘤在兔模型：技术问题

For ruptured human cerebral aneurysms endovascular embolization has become an equivalent alternative to aneurysm clipping.1 However, large clinical trials ...

科研

医学

Detection of Neuritic Plaques in Alzheimer's Disease Mouse Model

Alzheimer's disease (AD) is the most common neurodegenerative disorder leading to dementia. Neuritic plaque formation is one of the pathological hallmarks of Alzheimer's disease. The central component of neuritic plaques is a small filamentous protein called amyloid &beta; protein (A&beta;)1, which is derived from sequential proteolytic cleavage of the beta-amyloid precursor protein (APP) by &beta;-secretase and &gamma;-secretase. The amyloid hypothesis entails that A&gamma;-containing plaques as the underlying toxic mechanism in AD pathology2. The postmortem analysis of the presence of neuritic plaque confirms the diagnosis of AD. To further our understanding of A&gamma; neurobiology in AD pathogenesis, various mouse strains expressing AD-related mutations in the human APP genes were generated. Depending on the severity of the disease, these mice will develop neuritic plaques at different ages. These mice serve as invaluable tools for studying the pathogenesis and drug development that could affect the APP processing pathway and neuritic plaque formation. In this protocol, we employ an immunohistochemical method for specific detection of neuritic plaques in AD model mice. We will specifically discuss the preparation from extracting the half brain, paraformaldehyde fixation, cryosectioning, and two methods to detect neurotic plaques in AD transgenic mice: immunohistochemical detection using the ABC and DAB method and fluorescent detection using thiofalvin S staining method.

One of the pathological characteristics of AD is the formation of Amyloid &#x03B2; protein positive neuritic plaques. In this protocol we describe two methods to detect neuritic plaques in transgenic AD model mice: immunohistochemical detection using the ABC and DAB method and fluorescent detection using thioflavin S staining method.

在阿尔茨海默氏症小鼠模型神经炎斑检测

Alzheimer's disease (AD) is the most common neurodegenerative disorder leading to dementia. Neuritic plaque formation is one of the pathological hallmarks ...

神经科学

Visualization of Proprioceptors in Drosophila Larvae and Pupae

Proprioception is the ability to sense the motion, or position, of body parts by responding to stimuli arising within the body. In fruitflies and other insects proprioception is provided by specialized sensory organs termed chordotonal organs (ChOs) 2. Like many other organs in Drosophila, ChOs develop twice during the life cycle of the fly. First, the larval ChOs develop during embryogenesis. Then, the adult ChOs start to develop in the larval imaginal discs and continue to differentiate during metamorphosis.
The development of larval ChOs during embryogenesis has been studied extensively 10,11,13,15,16. The centerpiece of each ChO is a sensory unit composed of a neuron and a scolopale cell. The sensory unit is stretched between two types of accessory cells that attach to the cuticle via specialized epidermal attachment cells 1,9,14. When a fly larva moves, the relative displacement of the epidermal attachment cells leads to stretching of the sensory unit and consequent opening of specific transient receptor potential vanilloid (TRPV) channels at the outer segment of the dendrite 8,12. The elicited signal is then transferred to the locomotor central pattern generator circuit in the central nervous system.
Multiple ChOs have been described in the adult fly 7. These are located near the joints of the adult fly appendages (legs, wings and halters) and in the thorax and abdomen. In addition, several hundreds of ChOs collectively form the Johnston's organ in the adult antenna that transduce acoustic to mechanical energy 3,5,17,4.
In contrast to the extensive knowledge about the development of ChOs in embryonic stages, very little is known about the morphology of these organs during larval stages. Moreover, with the exception of femoral ChOs 18 and Johnston's organ, our knowledge about the development and structure of ChOs in the adult fly is very fragmentary.
Here we describe a method for staining and visualizing ChOs in third instar larvae and pupae. This method can be applied together with genetic tools to better characterize the morphology and understand the development of the various ChOs in the fly.

Visualization of Proprioceptors in Drosophila Larvae and Pupae

A method to immunostain and visualize chordotonal organs in larvae and pupae of Drosophila melanogaster is described.

可视化本体感受器<em&gt;果蝇</em&gt;幼虫和蛹

Proprioception is the ability to sense the motion, or position, of body parts by responding to stimuli arising within the body. In fruitflies and other ...

The Helsinki Rat Microsurgical Sidewall Aneurysm Model

Experimental saccular aneurysm models are necessary for testing novel surgical and endovascular treatment options and devices before they are introduced into clinical practice. Furthermore, experimental models are needed to elucidate the complex aneurysm biology leading to rupture of saccular aneurysms.
Several different kinds of experimental models for saccular aneurysms have been established in different species. Many of them, however, require special skills, expensive equipment, or special environments, which limits their widespread use. A simple, robust, and inexpensive experimental model is needed as a standardized tool that can be used in a standardized manner in various institutions.
The microsurgical rat abdominal aortic sidewall aneurysm model combines the possibility to study both novel endovascular treatment strategies and the molecular basis of aneurysm biology in a standardized and inexpensive manner. Standardized grafts by means of shape, size, and geometry are harvested from a donor rat&#39;s descending thoracic aorta and then transplanted to a syngenic recipient rat. The aneurysms are sutured end-to-side with continuous or interrupted 9-0 nylon sutures to the infrarenal abdominal aorta.
We present step-by-step procedural instructions, information on necessary equipment, and discuss important anatomical and surgical details for successful microsurgical creation of an abdominal aortic sidewall aneurysm in the rat.

Microsurgical sidewall aneurysms in rats are created by end-to-side anastomosis of an aortic graft to the abdominal aorta. We present step-by-step instructions and discuss anatomical and surgical details for successful experimental saccular aneurysm creation.

赫尔辛基鼠显微旁瘤模型

Experimental saccular aneurysm models are necessary for testing novel surgical and endovascular treatment options and devices before they are introduced ...

A Rabbit Venous Interposition Model Mimicking Revascularization Surgery using Vein Grafts to Assess Intimal Hyperplasia under Arterial Blood Pressure

Although vein grafts have been commonly used as autologous grafts in revascularization surgeries for ischemic diseases, the long-term patency remains poor because of the acceleration of intimal hyperplasia due to the exposure to arterial blood pressure. The present protocol is designed for the establishment of experimental venous intimal hyperplasia by interposing rabbit jugular veins to the ipsilateral carotid arteries. The protocol does not require surgical procedures deep in the body trunk and the extent of the incision is limited, which is less invasive for the animals, allowing long-term observation after implantation. This simple procedure enables researchers to investigate strategies to attenuate the progression of intimal hyperplasia of the implanted vein grafts. Using this protocol, we reported the effects transduction of microRNA-145 (miR-145), which is known to control the phenotype of vascular smooth muscle cells (VSMCs) from the proliferative to the contractile state, into harvested vein grafts. We confirmed the attenuation of intimal hyperplasia of vein grafts by transducing miR-145 before implantation surgery through the phenotype change of the VSMCs. Here we report a less invasive experimental platform to investigate the strategies that can be used to attenuate intimal hyperplasia of vein grafts in revascularization surgeries.

The present protocol aims to experimentally create venous intimal hyperplasia by subjecting veins to arterial blood pressure for developing strategies to attenuate venous intimal hyperplasia following revascularization surgery using vein grafts.

兔子静脉介词模型模仿再血管化手术使用静脉移植评估动脉血压下的影响增生

Although vein grafts have been commonly used as autologous grafts in revascularization surgeries for ischemic diseases, the long-term patency remains poor ...

Creation of Two Saccular Elastase-Digested Aneurysms with Different Hemodynamics in One Rabbit

Preclinical animal models with hemodynamic, morphologic, and histologic characteristics close to human intracranial aneurysms play a key role in the understanding of the pathophysiological processes and the development and testing of new therapeutic strategies. This study aims to describe a new rabbit aneurysm model that allows the creation of two elastase-digested saccular aneurysms with different hemodynamic conditions within the same animal.
Five female New Zealand white rabbits with a mean weight of 4.0 (&#177; 0.3) kg and mean age of 25 (&#177;5) weeks underwent microsurgical stump and bifurcation aneurysm creation. One aneurysm (stump) was created by right common carotid artery (CCA) exposure at its origin at the brachiocephalic trunk. A temporary clip was applied at the CCA origin and another, 2 cm above. This segment was treated with a local injection of 100 U of elastase for 20 min. A second aneurysm (bifurcation) was created by suturing an elastase-treated arterial pouch into the end-to-side anastomosis of the right CCA to left CCA. Patency was controlled by fluorescence angiography immediately after creation.
The average duration of surgery was 221 min. The creation of two aneurysms in the same animal was successful in all rabbits without complication. All aneurysms were patent immediately after surgery except for one bifurcation aneurysm, which showed an extreme tissue reaction due to elastase incubation and an immediate intraluminal thrombosis. No mortality was observed during surgery and up to one-month follow-up. Morbidity was limited to a transient vestibular syndrome (one rabbit), which recovered spontaneously within one day.
Demonstrated here for the first time is the feasibility of creating a two-aneurysm rabbit model with stump and bifurcation hemodynamic characteristics and highly degenerated wall conditions. This model allows the study of the natural course and potential treatment strategies on the basis of aneurysm biology under different flow conditions.

This protocol describes the steps for the creation of a rabbit model with two elastase-digested aneurysms with different hemodynamics (stump and bifurcation constellation). This allows the testing of novel endovascular devices in aneurysms with different angioarchitecture and hemodynamic conditions within a single animal.

在一只兔中产生两个具有不同血流动力学的囊状弹性蛋白酶消化动脉瘤

Preclinical animal models with hemodynamic, morphologic, and histologic characteristics close to human intracranial aneurysms play a key role in the ...

Microsurgical Creation of Giant Bifurcation Aneurysms in Rabbits for the Evaluation of Endovascular Devices

Giant aneurysms are dangerous lesions requiring endovascular treatment, with high rates of aneurysm recanalization and re-rupture. Reliable in vivo models are rare but are required for testing new endovascular devices.&#160;We demonstrate the technical aspects of the creation of giant bifurcation aneurysms in New Zealand white rabbits (2.5-5.5 kg). A 25-30 mm long venous pouch is taken from the external jugular vein, and a bifurcation between both carotid arteries is created microsurgically. The pouch is sutured in the bifurcation to mimic a giant aneurysm. This protocol summarizes our previously published standard technique for venous pouch true arterial bifurcation aneurysms and highlights its essential modification steps for giant aneurysms. Using this modified technique, we were able to create an animal model for giant aneurysms with high comparability to humans regarding the hemodynamics and coagulation systems. Furthermore, low morbidity and high aneurysm patency rates were achieved. The proposed giant aneurysm model offers an excellent possibility for testing new endovascular devices.

Here, we describe the technique for the microsurgical creation of giant bifurcation aneurysms in rabbits for the evaluation of endovascular devices.

显微外科在兔子中创建巨大分叉动脉瘤以评估血管内装置

Giant aneurysms are dangerous lesions requiring endovascular treatment, with high rates of aneurysm recanalization and re-rupture. Reliable in vivo models ...

Swine Models of Aneurysmal Diseases for Training and Research

Large animal models, specifically swine, are widely used to research cardiovascular diseases and therapies, as well as for training purposes. This paper describes two different aneurysmal swine models that may help researchers to study new therapies for aneurysmal diseases. These aneurysmal models are created by surgically adding a pouch of tissue to carotid arteries in swine. When the model is used for research, the pouch must be autologous; for training purposes, a synthetic pouch suffices.
First, the right external jugular vein (EJV) and right common carotid artery (CCA) must be surgically exposed. The EJV is ligated and a vein pouch fashioned from a short segment. This pouch is then sutured to an elliptical arteriotomy performed in the CCA. Animals must be kept heparinized during model creation, and local vasodilators may be used to decrease vasospasms. Once the suture is completed, correct blood flow should be inspected, checking for bleeding from the suture line and vessel patency. Finally, the surgical incision is closed by layers and an angiography performed to image the aneurysmal model.
A simplification of this aneurysmal carotid model that decreases invasiveness and surgical time is the use of a synthetic, rather than venous, pouch. For this purpose, a pouch is tailored in advance with a segment of a polytetrafluoroethylene (PTFE) prosthesis, one end of which is sutured close using polypropylene vascular suture and sterilized prior to surgery. This "sac" is then attached to an arteriotomy performed in the CCA as described. 
Although these models do not reproduce many of the physiopathological events related to aneurysm formation, they are hemodynamically similar to the situation found in the clinical setting. Therefore, they can be used for research or training purposes, allowing physicians to learn and practice different endovascular techniques in animal models that are close to the human system.

Description of two different aneurysmal swine models for neuroradiology training courses and research studies. This study provides evidence of the feasibility of these aneurysm porcine model creations and the reproducible methods that are close to the clinical setting.

Large animal models, specifically swine, are widely used to research cardiovascular diseases and therapies, as well as for training purposes. This paper ...

A Modified Technique for Arteriovenous Fistula Construction in Rabbits

Juxta-anastomotic stenosis is a challenging problem that often causes non-maturation and decreases the patency of an arteriovenous fistula (AVF). Injury to the veins and arteries during the operation and hemodynamic changes can lead to intimal hyperplasia, leading to juxta-anastomotic stenosis. To reduce injury to the veins and arteries during the operation, this study proposes a new modified no-touch technique (MNTT) for AVF construction that can decrease the rate of juxta-anastomotic stenosis and improve the AVF patency. To unravel the hemodynamic changes and mechanisms of the MNTT, this study presented an AVF procedure using this technique. Although this procedure is technically challenging, 94.4% procedural success was achieved after adequate training. Ultimately, 13 out of 34 rabbits had a functional AVF 4 weeks after the surgery, leading to a 38.2% AVF patency rate. However, at 4 weeks, the survival rate was 86.1%. Ultrasonography showed active blood flow through AVF anastomosis. Furthermore, the spiral laminar flow was observed in the vein and artery near the anastomosis, suggesting that this technique may improve the hemodynamics of the AVF. On histological observation, significant venous intimal hyperplasia was observed at the AVF anastomosis, whereas no significant intimal hyperplasia was observed at the proximal external jugular vein (EJV) of the anastomosis. This technique will improve the understanding of the mechanisms underlying the use of MNTT for AVF construction and provide technical support for the further optimization of the surgical approach in AVF construction.

The present protocol proposes the creation of an arteriovenous fistula in rabbits using a modified no-touch technique. The technique involves the side-to-side anastomosis of the common carotid artery and external jugular vein without the dissection of the perivenous tissues or cutting off the artery.

一种改良的兔动静脉瘘构建技术

Juxta-anastomotic stenosis is a challenging problem that often causes non-maturation and decreases the patency of an arteriovenous fistula (AVF). Injury ...

Developing an Experimental Aneurysm Model in a Rabbit Using an Elastase-Treated Vessel Pouch

<a href='https://app.jove.com/v/61157/arterial-pouch-microsurgical-bifurcation-aneurysm-model-in-the-rabbit'>Source: Wanderer, S., et al. Arterial Pouch Microsurgical Bifurcation Aneurysm Model in the Rabbit. J. Vis. Exp. (2020)</a>This video demonstrates the creation of an experimental aneurysm model in a rabbit using an elastase-treated vessel pouch. After excising a segment of the right CCA, the pouch is treated with elastase, then sutured to the left CCA to restore blood flow. The resulting stress on the weakened pouch walls induces aneurysm formation.