允许有针对性的大鼠模型血 - 脑屏障破坏神经血管治疗
Summary
血 – 脑屏障破坏，帮助某些药物输送到大脑。甘露醇动脉内交付收缩血管周围的细胞，以扰乱障碍。
Abstract
紧密连接的内皮细胞与基底膜和星形胶质细胞末端的脚环绕脑血管的形成血-脑屏障。选择性的阻挡排除分子根据它们的大小和电荷的血液和脑之间交叉。此功能可以阻碍治疗神经系统疾病的交付。化疗药物的一些，例如，将不会有效地穿过血-脑屏障到达肿瘤细胞2。因此，改善药物透过血 – 脑屏障的交付是感兴趣的区域。
为提高药物的交付到大脑的最普遍的方法是直接脑输注和血-脑屏障破坏3。直接脑内输液保证疗法到达大脑，然而，这种方法具有的能力是有限的药物分散4。血 – 脑屏障的中断（BBBD）人低点流直接从循环系统的药物 到大脑，从而更有效地达到分散的肿瘤细胞。三种方法的屏障破坏，渗透屏障破坏，药物屏障破坏，聚焦超声微泡。渗透破坏，开创Neuwelt，使用高渗溶液，25％甘露醇脱水的细胞血 – 脑屏障，使他们萎缩，瓦解他们的紧密连接。屏障破坏，也可以完成药理上具有血管活性化合物5，如组胺，缓激肽6。然而，该方法中，是有选择性的，主要用于脑肿瘤屏障7。此外，RMP-7，血管舒缓激肽的肽的类似物，被发现时相比，头-对-头与渗透BBBD与25％甘露糖醇8差。聚焦超声（FUS）与微泡的超声造影剂的结合，另一种方法，也被证明可逆打开的血-脑屏障。在比较FUS，不过，25％甘露醇有一个较长的历史，在人类患者中的安全性，它使一个行之有效的工具转化研究10-12。
为了实现BBBD，甘露糖醇，必须以很高的速率直接进入大脑的动脉循环交付。在人类中，血管内导管被引导到大脑，其中可以实现快速，直接流。 “本协议模型人BBBD尽可能接近。经过切口下降到常见的颈动脉分叉处，导管插入逆行进入ECA和用于提供甘露糖醇直接到内颈动脉（ICA）的循环。丙泊酚和N 2 O麻醉用于自己的能力发挥最大的效益屏障破坏13。如果执行得当，此过程有安全，有效，可逆打开血 – 脑屏障和即兴表演的能力e的药物，通常不会到达大脑8,13,14交付。
Protocol
1。准备过程的动物和设备手术开始之前，准备手术区和动物。使颈动脉导管插入到一端12“PE50管23隔距的钝针剪切在导管的另一端的约45°的斜角。消毒设备之前的程序。戴上头发阀盖，外科口罩和无菌手套。 表面上放置一个加热垫，手术将进行。激活它，让它温暖。覆盖的区域的吸收性板凳垫。 请确认你有25％甘露醇溶液中无晶体。如果晶体存在，溶解由小瓶放置在80℃的?…
Representative Results
图1。可视化通过血-脑屏障破坏Evans蓝染料外渗。Evans蓝染料是与白蛋白结合，未外渗进入大脑在生理条件下的颜料。血 – 脑屏障的大脑的一侧上的中断允许Evans蓝进入和染色的打乱的半球的蓝色，而在非破坏的半球不变。因此，这是一个有用的标记血-脑屏障破坏， 图1A是一个示例的脑无血-脑…
Discussion
有几个的最大化疗效BBBD的装置。这是重要的，以尽量减少在切口向下阶段出血。血压和心脏速率可以由大出血的影响，这些因素已知影响程度BBBD 13的 。出血可减少通过使用缝合线结扎大血管，如甲状腺上和枕动脉，必须除以。此外，电，可以用来划分的血管和剖析领域有丰富的血液供应。同样重要的是，以保持空气和固体放入动物的所有行，满分 – 尤其是颈动脉导管。与甘露醇快速工?…
Disclosures
The authors have nothing to disclose.
Acknowledgements
这项工作是支持的JB马歇尔基金会。
Materials
| Material Name | Company | Catalogue number | Comment |
| Long Evans rat | Harlan Laboratories | 210-250 g, male | |
| PE 50 Tubing | Beckton-Dickinson | ||
| 18 gauge x 2.5″ IV catheter | Terumo | For ET tube | |
| 30″ IV extension sets | Abbott | ||
| 26 gauge veterinary IV catheter | Monoject | ||
| Evans blue dye | Sigma | E2129 | |
| Bipolar | Codman | ||
| Filter, 5 μm | Braun |
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Cite This Article
Martin, J. A., Maris, A. S., Ehtesham, M., Singer, R. J. Rat Model of Blood-brain Barrier Disruption to Allow Targeted Neurovascular Therapeutics. J. Vis. Exp. (69), e50019, doi:10.3791/50019 (2012).