Tummala Saigiridhar, Hill Brent J F
Department of Biology, University of Central Arkansas, 201 Donaghey Avenue, Conway, AR 72035, USA.
Vascul Pharmacol. 2007 May;46(5):346-52. doi: 10.1016/j.vph.2006.12.001. Epub 2006 Dec 9.
We have previously reported that organ cultured coronary arteries from market-age pigs (6-9 months of age) exhibit an enhanced contraction to the atherosclerotic-associated peptide, endothelin-1 (ET-1). The objective of this study was to investigate the interaction of 17beta-estradiol with ET-1 in organ cultured coronary arteries from older female pigs (3-4 years old). A cumulative concentration-response relationship (1 x 10(-9) M to 3 x 10(-7) M) was generated to ET-1, and the isometric tension measured in fresh and organ cultured (4 days at 37 degrees C) arterial rings that were each pre-incubated for 50 min in different concentrations (1 x 10(-9) M to 1 x 10(-5) M) of 17beta-estradiol. Compared to freshly used arteries, culturing induced a 2-fold increase in tension development to ET-1 (3 x 10(-7) M). Although 17beta-estradiol previously relaxed pre-constricted (with a 60 mM KCl solution) arteries, it did not affect the constrictive response to ET-1. Also, using an ET-1 ELISA we found that 17beta-estradiol did not effect ET-1 production in intact arteries. Our results indicate that 17beta-estradiol does not attenuate the production and constrictive properties of ET-1 in coronary arteries demonstrating a dedifferentiated cell phenotype.
我们之前曾报道，来自市场年龄猪（6 - 9月龄）的器官培养冠状动脉对动脉粥样硬化相关肽内皮素-1（ET-1）表现出增强的收缩反应。本研究的目的是调查17β-雌二醇与ET-1在老年雌性猪（3 - 4岁）的器官培养冠状动脉中的相互作用。生成了ET-1的累积浓度-反应关系（1×10⁻⁹ M至3×10⁻⁷ M），并在新鲜的和器官培养的（37℃下培养4天）动脉环中测量等长张力，这些动脉环分别在不同浓度（1×10⁻⁹ M至1×10⁻⁵ M）的17β-雌二醇中预孵育50分钟。与刚使用的动脉相比，培养使对ET-1（3×10⁻⁷ M）的张力发展增加了2倍。尽管17β-雌二醇先前可使预收缩的（用60 mM KCl溶液）动脉舒张，但它并不影响对ET-1的收缩反应。此外，使用ET-1 ELISA我们发现17β-雌二醇对完整动脉中ET-1的产生没有影响。我们的结果表明，在表现出去分化细胞表型的冠状动脉中，17β-雌二醇不会减弱ET-1的产生和收缩特性。
