Polosa R, Hasani A, Pavia D, Agnew J E, Lai C K, Clarke S W, Holgate S T
Immunopharmacology Group, Southampton General Hospital.
Thorax. 1992 Nov;47(11):952-6. doi: 10.1136/thx.47.11.952.
Bradykinin, a nonapeptide that contributes as a mediator to the pathogenesis of asthma, may affect lung mucociliary clearance, as it has been shown to be a potent secretagogue in canine airways and in human nasal mucosa in vivo. To evaluate this possibility the effect of inhaled bradykinin on mucociliary clearance has been studied in 10 healthy volunteers.
Subjects attended the laboratory on two occasions to take part in tracheobronchial clearance studies using a non-invasive radioisotopic technique. Inhalation of radioaerosol was followed 30 minutes later by inhalation of either bradykinin (8 mg/ml) or vehicle placebo in a randomised, double blind fashion. After each inhalation the number of coughs was recorded. Whole lung radioactivity was measured every half hour for six hours with two collimated scintillation counters, and a tracheobronchial clearance curve was plotted for each subject on each occasion.
Mucociliary clearance, expressed as the area under the tracheobronchial radioaerosol retention curve calculated for the first six hours (AUC0-6h), was greater in nine out of 10 subjects after inhalation of bradykinin than after placebo. The median values (range) for AUC0-6h were significantly reduced from 126% (78-232%)/h with placebo to 87% (51-133%)/h with bradykinin.
It is concluded that acute exposure to inhaled bradykinin accelerates tracheobronchial clearance in normal human airways.
缓激肽是一种九肽，作为介质参与哮喘的发病机制，可能影响肺黏液纤毛清除功能，因为在体内实验中已表明它在犬气道和人鼻黏膜中是一种强效促分泌素。为评估这种可能性，对10名健康志愿者吸入缓激肽对黏液纤毛清除功能的影响进行了研究。
受试者分两次到实验室，采用无创放射性同位素技术参与气管支气管清除研究。在吸入放射性气雾剂30分钟后，以随机、双盲方式吸入缓激肽（8毫克/毫升）或赋形剂安慰剂。每次吸入后记录咳嗽次数。用两个准直闪烁计数器每半小时测量全肺放射性，每次为每位受试者绘制气管支气管清除曲线。
以吸入后前6小时计算的气管支气管放射性气雾剂滞留曲线下面积（AUC0 - 6h）表示的黏液纤毛清除功能，10名受试者中有9名吸入缓激肽后的清除功能比吸入安慰剂后更强。AUC0 - 6h的中位数（范围）从安慰剂组的126%（78 - 232%）/小时显著降至缓激肽组的87%（51 - 133%）/小时。
得出的结论是，急性吸入缓激肽可加速正常人气道的气管支气管清除功能。
