肱血流介导的扩张和大鼠股浅动脉超声评估
Summary
在人类血管内皮功能的非侵入性的评估可以通过血流介导的扩张的技术来确定。虽然千研究中使用了该技术，没有研究在大鼠进行这种技术非侵入。下面的文章介绍肱血流介导的扩张和大鼠股浅动脉无创测量。
Abstract
Arterial vasodilation to increases in wall shear rate is indicative of vascular endothelial function. In humans, the non-invasive measurement of endothelial function can be achieved by employing the flow-mediated dilation technique, typically performed in the brachial or superficial femoral artery. Briefly, a blood pressure cuff placed distal to an ultrasound probe is inflated to a suprasystolic pressure, which results in limb ischemia. After 5 min of occlusion the cuff is deflated, resulting in reactive hyperemia and increases in wall shear rate that signal vasodilatory molecules to be released from the endothelium eliciting vasodilation. Despite the thousands of studies performing flow-mediated dilation in humans, surprisingly, no studies have performed this technique non-invasively in living rats. Considering the recent shift in focus to translational research, the establishment of guidelines for non-invasive measurement of flow-mediated dilation in rats and other rodents would be extremely valuable. In the following article, a protocol is presented for the non-invasive measurement of flow-mediated dilation in brachial and superficial femoral arteries of rats, as those sites are most commonly measured in humans.
Introduction
血管内皮是蜂窝单层该线条动脉的内腔并且是血管功能的重要调节剂。有从内皮释放众多分子导致血管直径的调制。在这些分子，一氧化氮（NO），似乎是在响应于刺激从血管内皮释放的主血管舒张分子（例如，胰岛素，乙酰胆碱，或剪切应力的变化）1。在血管内皮细胞，编号是由酶产生内皮NO合酶（eNOS）和随后从血管内皮细胞2释放。否扩散到血管平滑肌，其中它引起松弛和增加的血管直径3。
内皮功能障碍可以在利用血流介导的舒张（FMD）技术4,5-人类非侵入性进行评估。口蹄疫已经提出来表示一个功能生物测定内皮衍生在人类中NO的生物利用度，且通常评估在下列一〜5分钟肢闭塞6响应于反应性充血肱或股浅动脉。反应性充血增加了被转导至内皮细胞的7层的剪切力，信令NO 8的释放。虽然近年来，血管舒张由NO释放发起的比重一直争论不休9,10，口蹄疫表明内皮依赖性扩张，并一直被证明预测心血管事件11-13。
迄今为止，成千上万的研究已经使用的口蹄疫技术用于人类血管内皮功能的非侵入性测量。考虑到在重点转化研究近期的转变，对口蹄疫的啮齿类动物的非侵入性测量准则将是非常有价值的。与平移方法保持一致，该协议是建立在肱动脉和苏佩FMD的测量大鼠rficial股动脉，由于这些网站都是人类最常用的测量。在大鼠一个强大的和可重复的口蹄疫响应这个协议的结果，然而，在大鼠口蹄疫测量技术要求高，可能是困难的其他研究者没有视频演示复制。因此，下面的文章将演示口蹄疫肱和大鼠股浅动脉血管无创测量的方法。
Protocol
Representative Results
Discussion
在本研究中，FMD的一种非侵入性测量表现在肱动脉和大鼠股浅动脉。类似于人类6，以下5分钟闭塞期内，在血流速度（即，反应性充血），从而在动脉壁上导致动脉的后续血管舒张增加的剪切速率迅速增加。口蹄疫是在肱动脉和股浅动脉两个观察。此外，还有在FMD动脉之间有很强的关系。虽然最高剪切速率在股浅动脉较高，口蹄疫归到最高剪切速率保持动脉之间牢固的关系。总之，这些结…
Divulgations
The authors have nothing to disclose.
Acknowledgements
All animal imaging was performed at the Small Animal Imaging Core Facility, University of Utah.
This study was funded in part by grants from the National Institutes of Health (R21 AG043952, R01 AG040297, K01 AG046326, K02 AG045339, and R01 DK100505).
Materials
| Vevo 2100 High Resolution Micro-Ultrasound Imaging System | VisualSonics, Toronto, ON, CAN | ||
| MicroScan Ultra-High Frequency Linear Array Transducer – MS-700 30-70 MHz | VisualSonics, Toronto, ON, CAN | ||
| Vevo Imaging Station | VisualSonics, Toronto, ON, CAN | ||
| Thermasonic gel warmer | Parker Laboratories, Fairfield, NJ, USA | 82-03 | Optional |
| Signacreme electrode cream | Parker Laboratories, Fairfield, NJ, USA | 17-05 | |
| Transpore surgical tape | 3M, Maplewood, MN, USA | 1527-1 | |
| Depilatory cream (e.g., Nair) | General supply | ||
| Cotton swabs | General supply | ||
| Ultrasound gel | General supply | ||
| Standard vascular occluder, 10 mm lumen diameter | Harvard Apparatus, Holliston, MA, USA | 62-0115 | |
| 10 ml syringe with Luer-Lok tip | General Supply | Used for occlusion cuff apparatus | |
| Paperclip | General Supply | Used for occlusion cuff apparatus | |
| Hypodermic needle – 18 gauge | General Supply | Used for occlusion cuff apparatus | |
| Medium binder clip | General Supply | Used for occlusion cuff apparatus |
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