Comparison of vasoactive intestinal peptide and isoproterenol relaxant effects in isolated cat airways.
Comparison of vasoactive intestinal peptide and isoproterenol relaxant effects in isolated cat airways.
复制标题
血管活性肠肽和异丙肾上腺素在离体猫气道中的松弛作用比较。
DOI：
10.1152/jappl.1984.56.4.986
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发表时间：
1984
期刊：
影响因子：
--
通讯作者：
Diamond,L
中科院分区：
文献类型：
--
作者：
Altiere,RJ;Diamond,L
血管活性肠肽(VIP)是一种存在于包括肺在内的哺乳动物组织中的内源性多肽，是一种有效的血管舒张剂。在预缩缩段的猫气管、肺门支气管段和肺内支气管段，比较了VIP的浓度-松弛曲线和异丙肾上腺素的浓度-松弛曲线。VIP和异丙肾上腺素对肺外呼吸道的松弛作用几乎相同。在逐渐变小的呼吸道中，观察到对VIP的敏感性降低，这表明VIP诱导的反应存在区域性差异。相反，组织对异丙肾上腺素的反应没有区域性差异。心得安(10(-6)M)可拮抗异丙肾上腺素的松弛反应，但对VIP的量效曲线无影响。吲哚美辛(10(-5)M)可完全阻止外源性花生四烯酸的反应，但不能抑制VIP诱导的松弛。禽胰多肽可抑制猫对VIP的血管扩张反应，但不能拮抗VIP引起的气道平滑肌松弛。这些结果表明，VIP是一种有效的体外猫气管-支气管肌松弛药，其松弛作用不是通过β-肾上腺素能受体或前列腺素介导的。鉴于前人对VIP免疫反应在猫肺内气道周围神经定位的报道，本研究结果提示VIP可能参与了该物种气道张力的调节。
Vasoactive intestinal peptide (VIP), an endogenous peptide found in mammalian tissues including the lung, is a potent relaxant of smooth muscle. In precontracted segments of cat trachea, hilar bronchus, and intrapulmonary bronchus, concentration-relaxation curves to VIP were compared with those produced by isoproterenol. VIP and isoproterenol were nearly equipotent in causing relaxation of extrapulmonary airways. A decreasing sensitivity to VIP was observed in progressively smaller airways, suggesting regional variation in VIP-induced responses. In contrast, tissues showed no regional differences in response to isoproterenol. Propranolol (10(-6) M), which antagonized relaxation responses to isoproterenol, had no effect on VIP concentration-response curves. Indomethacin (10(-5) M) completely prevented responses to exogenous arachidonic acid but did not inhibit VIP-induced relaxation. Avian pancreatic polypeptide, which has been reported to inhibit vasodilator responses to VIP in the cat, was unable to antagonize airway smooth muscle relaxation induced by VIP. These results demonstrate that VIP is a potent relaxant of cat tracheobronchial smooth muscle in vitro and that the relaxant effects of this peptide are not mediated through beta-adrenergic receptors or by prostaglandins. In view of previous reports on the localization of VIP immunoreactivity in nerves around airways in cat lung, results of the present study suggest that VIP may participate in the regulation of airway tone in this species.