豚鼠气道上皮对钾通道开放剂Rp52891作用的影响

为了观察气道上皮对钾通道开放剂Ｒｐ５２８９１作用的影响，将正常豚鼠和致敏豚鼠的气管螺旋条随机分成完整上皮组和去除上皮组，用组胺诱发收缩后，分别加入Ｒｐ５２８９１、氨茶碱及异丙肾上腺素，测定气管螺旋条对组胺及上述三种物质的反应。结果发现，正常豚鼠和致敏豚鼠气管螺旋条对组胺的反应性在两组间差异无显著性（Ｐ＞０．０５），Ｒｐ５２８９１对去除上皮组的舒张作用明显弱于完整上皮组（Ｐ＜０．０５），氨茶碱和异丙肾上腺素的舒张作用在两组间差异无显著性（Ｐ＞０．０５）。提示Ｒｐ５２８９１可直接舒张气道平滑肌，气道上皮参与介导其舒张作用。

THE EFFECT OF EPITHELIUM ON INHIBITION OF HISTAMINE INDUCED CONTRACTION OF GUINEA PIG ISOLATED TRACHEA BY POTASSIUM CHANNEL OPENER Rp 52891

To evaluate whether the relaxant effect of Rp 52891 on isolated normal or sensitized guinea pigs trachea is influenced by the removal of airway epithelium, twenty four normal and sensitized guinea pigs were randomly divided into two groups: epithelium intact trachea and epithelium denuded trachea. The effect of Rp 52891 on contraction elicited by histamine in epithelium intact and epithelium denuded trachea was investigated, and it was compared with that of aminophylline or isoprenaline. The results revealed that there was no significant difference in histamine induced contractile response between normal and sensitized isolated trachea. The inhibitory effect of Rp 52891 on the contractile response of histamine was significantly reduced by removing the epithelium but that of aminophylline or isoprenaline was not changed. These results suggested that Rp 52891 may directly relax the airway smooth muscle of guinea pigs in vitro, the epithelium of guinea pigs trachea may modulate the relaxant effect of Rp 52891.