肠系膜动脉收缩和舒张的研究，使用自动线Myography
Summary
一个孤立的肠系膜动脉的力测量的自动化myography方法描述。它采用一个Mulvany哈尔彭自动双丝肌动描记510A福林和钙，以确定响应。该方法允许等距反应一致，以激动剂决心在小血管的直径为60 – 300微米，独立。
Abstract
如肠系膜动脉的近端阻力血管，作出重大贡献的外周阻力。这些小血管的功能，主要是在指挥根据到身体的总体要求各个器官的血流量，直径100-400微米之间。大鼠肠系膜动脉的直径大于100微米的。贝文和奥谢尔2所提出的方法的基础上，首先由 1 Mulvay和哈尔彭所描述的，是myography技术。该技术提供等距条件下，大幅缩短的肌肉准备阻止的小型船只的信息。由于力的生产和船只不同受体激动剂的敏感性依赖于伸展的程度，按照积极紧张长度关系，这是必不可少的等距条件下进行收缩的研究，以防止符合安装电线。不锈钢丝是首选，因为后者的氧化，从而影响记录反应3钨丝，该技术允许安装船只激动剂诱导的收缩比较，以获取证据表明血管平滑肌细胞受体的正常功能。
在几项研究中，我们已经表明phenylyephrine承包的，孤立的肠系膜动脉累积浓度的钙（钙2 + E）除了放宽。结果导致我们得出结论，它表达的G蛋白偶联的Ca 2 +敏感受体（CAR），血管周围的感官神经，调解这个血管舒张反应。使用自动线myography方法，我们在这里展示，从只Wistar Dahl盐敏感（DS）和Dahl盐抵抗（DR）的肠系膜动脉的大鼠有不同的反应的Ca 2 + E 。从大鼠组织表现出更高的Ca 2 +敏感性相比，DR和DS。减少从DS大鼠肠系膜动脉车表达与减少的Ca 2 + E -诱导孤立的，承包前动脉松弛。数据表明，汽车是需要放宽增加肾上腺素基调下肠系膜动脉，在高血压发生，并表示在汽车的信号转导通路在达尔动物的固有缺陷，这是更为严重的DS。
肠系膜阻力动脉和类似的小血管和比较不同的受体激动剂和/或拮抗剂在确定血管反应性的体外的方法是有用的，可以很容易地和一贯的评估并排侧6,7,8。
Protocol
Discussion
高血压是心血管，脑和肾脏的发病率/死亡率的首要原因。高血压的发生是在人口高盐敏感性高血压是特别高，在人口老龄化，更多的黑人比白人流行。这被认为是由于对黑人的倾向保留在自己的肾脏 9钠。盐敏感性是肾脏疾病的一个主要因素，并与血管内皮功能障碍有关，但机制尚不完全清楚。在我们实验室最近的研究显示，高盐饮食可减少组织间液的Ca 2 +浓度（[Ca2 2 <su…
Offenlegungen
The authors have nothing to disclose.
Acknowledgements
描述该项目奖号码R01 HL064761，R25 HL059868 1SC1 HL099139和P20 MD000175形式国立卫生研究院的支持。内容完全是作者的责任，并不一定代表国立卫生研究院的官方意见。
Materials
| Name of equipment/ reagent | Company | Catalogue number | Comments(optional) |
|---|---|---|---|
| Auto Dual Wire Myograph System-510A DMT-USA, Inc. | Atlanta, GA. | 100151 | |
| PowerLab/4SP Data Acquisition System | ADInstruments, Colorado Springs, CO. | ML750 | New models with 4-16 input channels are available. |
| Dell Dimension XPS Gen 4 Computer | Dell | ||
| Stemi SV II (Apo) Dissection Microscope with Ocular | Carl Zeiss International. | ||
| Wistar, Dahl salt-sensitive, Dahl salt-resistant rats | Harlan Sprague Dawley, Indianapolis, IN. | ||
| Rodent chow | Harland Tekland, Madison, WI. | ||
| Phenylephrine | Sigma-Aldrich, St. Louis, MO. | ||
| Other chemicals | All chemicals used were of the purest grades available commercially. |
Referenzen
- Mulvany, M. J., Halpern, W. Mechanical properties of vascular smooth muscle cells in situ. Nature. 260, 617-619 (1976).
- Bevan, J. A., Osher, J. V. A direct method for recording tension changes in the wall of small blood vessels in vitro. Agents Actions. 2, 257-260 (1972).
- Mulvany, M. J. Procedures for investigating of small vessels using small vessel myograph. DMT Danish Myo Technology. , (2004).
- Angus, J. A., Wright, C. E. Techniques to study the pharmacodynamics of isolated large and small blood vessels. J. Pharmacol. Toxicol. Methods. 44, 395-407 (2000).
- Halpern, W., Mulvany, M. J., Warshaw, D. M. Mechanical properties of smooth muscle cells in the walls of arterial resistance vessels. J. Physiol. 275, 85-101 (1978).
- Lindhorst, J., Alexander, N., Blignaut, J., Rayner, B. Differences in hypertension between blacks and whites: an overview. Cardiovasc. J. Afr. 18, 241-247 (2007).
- Eley, S. L., Allen, C. M., Williams, C. L., Bukosi, R. D., Pointer, M. A. Action of thiazide on renal interstitial calcium. Am. J. Hypertens. 21, 814-819 (2008).
- Palmer, C. E., Rudd, M. A., Bujoski, R. D. Renal interstitial Ca2+ during sodium loading of normotensive and Dal-salt hypertensive rats. Am. J. Hypertens. 16, 771-776 (2003).
- Hurwitz, S. Homeostatic control of plasma calcium concentration. Crit. Rev. Biochem. Mol. Biol. 31, 41-100 (1996).
- Brown, E. M., MacLeod, R. J. Extracellular sensing and extracellular calcium signaling. Physiol. Rev. 81, 239-297 (2001).
- Breitwieser, G. E. Extracellular calcium as an integrator of tissue function. Int. J. Biochem. Cell Biol. 40, 1467-1480 (2008).
- Mupanomunda, M. M., Wang, Y., Bukoski, R. D. Effect of chronic sensory denervation on Ca2+-induced relaxation of isolated mesenteric resistance arteries. Am. J. Physiol. 274, 1655-1661 (1998).
- Mupanomunda, M. M., Ishioka, N., Bukoski, R. D. Interstitial Ca2+ undergoes dynamic changes sufficient to stimulate nerve-dependent Ca2+-induced relaxation. Am. J. Physiol. 276, 1035-1042 (1999).
- Mupanomunda, M. M., Tian, B., Ishioka, N., Bukoski, R. D. Renal interstitial Ca2+. Am. J. Physiol. Renal Physiol. 278, F644-F649 (2000).
- Awumey, E. M., Hill, S. K., Diz, D. I., Bukoski, R. D. Cytochrome P-450 metabolites of 2-arachidonoylglycerol play a role in Ca2+-induced relaxation of rat mesenteric arteries. Am. J. Physiol. Heart Circ. Physiol. 294, 2363-2370 (2008).
- Chen, W., Bergsman, J. B., Wang, X., Gilkey, G., Pierpoint, C. R., Daniel, E. A., Awumey, E. M., Dauban, P., Dodd, R. H., Ruat, M., Smith, S. M. Presynaptic external calcium signaling involves the calcium-sensing receptor in neocortical nerve terminals. PloS One. 5, e8563-e8563 (2010).
- Bukoski, R. D. The perivascular sensory nerve Ca2+ receptor and blood pressure regulation: a hypothesis. Am. J. Hypertens. 11, 1117-1123 (1998).
- Bukoski, R. D. Dietary Ca2+ and blood pressure: evidence that Ca2+-sensing receptor activated sensory nerve dilator activity couples changes in interstitial Ca2+ with vascular. 16, 218-221 (2001).
