Heterogeneity in the effects of epithelium removal in the canine bronchial tree.
Heterogeneity in the effects of epithelium removal in the canine bronchial tree.
复制标题
犬支气管树上皮去除效果的异质性。
DOI：
10.1152/jappl.1987.63.6.2510
复制
发表时间：
1987
期刊：
影响因子：
--
通讯作者：
Vanhoutte,PM
中科院分区：
文献类型：
--
作者：
Stuart-Smith,K;Vanhoutte,PM
探讨了去除气道上皮对犬气道收缩和舒张激动剂反应的影响。研究了三个级别的犬支气管：第二级别（叶支气管）、第三级别（段支气管）和第四级别（亚段支气管）。将具有和不具有上皮的成对组织环放置在用95%O2 - 5%CO2充气的生理盐溶液中的器官室中，并保持在37 ℃。对于二阶和三阶支气管，上皮细胞去除引起5-羟色胺，组胺和乙酰胆碱的浓度-效应曲线显著左移。在四阶支气管中，任何收缩激动剂均无显著变化。异丙肾上腺素（在收缩引起的乙酰胆碱）诱导浓度依赖性舒张，显着大于在那些没有上皮的支气管。这种效应在四级支气管中最为突出。这些结果表明：1）犬气道上皮细胞释放松弛因子，2）在较大气道中，主要作用是减少收缩反应，3）在较小气道中，主要作用是增强松弛反应。
The effect of removing the airway epithelium on the responses of canine airways of decreasing diameter to contractile and relaxing agonists was explored. Three orders of canine bronchus were studied: second order (lobar bronchus), third order (segmental bronchus), and fourth order (subsegmental bronchus). Paired rings of tissue, with and without epithelium, were placed in organ chambers in physiological salt solution gassed with 95% O2–5% CO2 and maintained at 37 degrees C. For second- and third-order bronchi, epithelium removal caused significant left-ward shifts of the concentration-effect curves for 5-hydroxytryptamine, histamine, and acetylcholine. In fourth-order bronchi, there was no significant shift for any of the contractile agonists. Isoproterenol (during contractions evoked by acetylcholine) induced concentration-dependent relaxations that were significantly greater in bronchi with than in those without epithelium. This effect was most prominent in fourth-order bronchi. These results suggest that 1) the canine airway epithelium releases a relaxing factor, 2) in larger airways the major effect is reduction of contractile responses, and 3) in smaller airways the major effect is enhancement of relaxing responses.