Manning P J, Jones G L, Otis J, Daniel E E, O'Byrne P M
Department of Medicine, McMaster University, Hamilton, Ontario, Canada.
Eur J Pharmacol. 1990 Mar 13;178(1):85-9. doi: 10.1016/0014-2999(90)94796-z.
Reduced smooth muscle contractile responses to agonists occur in the presence of epithelium, perhaps due to the release of an epithelium-derived relaxing factor (EpDRF). It is not clear whether the release of EpDRF requires the direct attachment of the epithelium to the smooth muscle. In the present study, using isolated canine tracheal smooth muscle strips, we examined whether the inhibitory effects of airway mucosa require the attachment of the mucosa to smooth muscle. The smooth muscle contractile responses to acetylcholine and histamine were reduced in the presence of airway mucosa, whether the mucosa was attached or in close proximity. The inhibitory effect mediated by the airway mucosa therefore is not dependent on mucosal attachment to smooth muscle. This phenomenon appears to be due to the release of a soluble, short-acting mediator from the airway mucosa.
在存在上皮的情况下，平滑肌对激动剂的收缩反应减弱，这可能是由于上皮衍生的舒张因子（EpDRF）的释放所致。目前尚不清楚EpDRF的释放是否需要上皮直接附着于平滑肌。在本研究中，我们使用分离的犬气管平滑肌条，研究气道黏膜的抑制作用是否需要黏膜附着于平滑肌。无论黏膜是附着还是紧邻，在气道黏膜存在的情况下，平滑肌对乙酰胆碱和组胺的收缩反应均减弱。因此，气道黏膜介导的抑制作用并不依赖于黏膜与平滑肌的附着。这种现象似乎是由于气道黏膜释放了一种可溶性、短效介质所致。
