呼吸道中蛋白酶激活受体的保护作用
1Department of Pharmacology, University of Melbourne, Parkville, Victoria, Australia. t.cocks@pharmacology.unimelb.edu.au
Nature
|March 23, 1999
概括
素激活了呼吸道上皮质中的蛋白酶激活受体2 (PAR2),触发了前列腺素E2 (PGE2) 释放以保护呼吸道. 这种机制抑制了支气管收缩,突出了呼吸道中的新型保护途径.
科学领域:
- 肺部医学 肺部医学
- 细胞生物学 细胞生物学
- 胃肠病学 胃肠病学
背景情况:
- 上肠使用前列腺素E2 (PGE2) 和蛋白酶激活受体 (PARs) 进行表皮细胞对素的保护.
- 空气道上皮与肠道上皮有相似之处,并且表达PAR2,这是这种保护机制中的关键受体.
- 气道上皮质是PGE2的重要来源,这表明它可能在气道细胞保护中发挥作用.
研究的目的:
- 调查支气管上皮PAR2在前列腺依赖性气道细胞保护中的作用.
- 为了确定素激活的PAR2能否诱导气道中的保护性反应.
主要方法:
- 免疫组织化学评估PAR2和素 (素) 在呼吸道表皮中的同位.
- 从各种物种 (老鼠,老鼠,几内亚猪,人类) 中分离的呼吸道制剂的ex vivo研究,以测量对PAR2激活的反应.
- 在麻醉大鼠体内研究,以评估PAR2激活对支气管收缩的影响.
- 涉及PAR2脱敏的实验,以评估恢复机制.
主要成果:
- 呼吸道上皮质中PAR2的激活会触发循环氧化酶产物的释放,导致呼吸道放松.
- PAR2激活显著抑制隔离的呼吸道和体内呼吸道中的支气管收缩.
- 在 PAR2 脱敏后,通过 de novo 蛋白质合成和贩运,对素的反应迅速恢复.
结论:
- 皮质PAR2激活启动了一个强大的,依赖于前列腺素的支气管保护反应.
- 从上皮层释放的素可以激活PAR2,从而保护呼吸道并抑制支气管收缩.
- 这条通道代表了气道细胞保护的重要生理机制.
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