Simons F E, Soni N R, Watson W T, Becker A B
Section of Allergy and Clinical Immunology, Faculty of Medicine, University of Manitoba, Canada.
J Allergy Clin Immunol. 1992 Nov;90(5):840-6. doi: 10.1016/0091-6749(92)90110-n.
In adults with asthma, the selective beta 2-adrenergic agonist salmeterol has a prolonged bronchodilator and bronchoprotective effect. To date, there are few published studies of salmeterol in children.
We compared the bronchodilator and bronchoprotective effects of salmeterol, 25 and 50 micrograms, with salbutamol, 200 micrograms, and with placebo, administered via metered-dose inhaler, in a randomized, double-blind, within-patient, four-way crossover, single-dose study in 20 children.
Mean baseline forced expiratory volume in 1 second (FEV1) and PC20 methacholine were not significantly different (p > 0.05) on the 4 study days, and did not change significantly after placebo. FEV1 increased significantly from 5 to 30 minutes after salbutamol, and from 5 minutes to 12 hours after 25 micrograms or 50 micrograms salmeterol, compared with placebo. After 25 micrograms or 50 micrograms salmeterol, FEV1 was significantly lower than after salbutamol at 5 and 10 minutes, did not differ from salbutamol at 30 minutes, and was significantly greater than after salbutamol from 3 to 12 hours. No significant difference occurred between the effect of 25 micrograms salmeterol and the effect of 50 micrograms salmeterol on FEV1. After salbutamol, there was a significant increase in PC20 only at 30 minutes. After 25 micrograms or 50 micrograms salmeterol, PC20 increased significantly from 30 minutes to 12 hours. Salmeterol, 25 micrograms and 50 micrograms provided significantly greater bronchoprotection than salbutamol from 3 to 12 hours and from 30 minutes to 12 hours, respectively. Salmeterol, 50 micrograms, provided significantly better bronchoprotection than 25 micrograms salmeterol from 30 minutes to 12 hours. The amount of change in PC20 accounted for by change in FEV1 varied from 14% to 28%, indicating that protection against bronchoconstriction was not entirely dependent on bronchodilation.
Salmeterol is a potent, long-acting bronchodilator, with a slower onset of bronchodilation than salbutamol. It provides significantly greater and longer-lasting protection against bronchoconstriction than salbutamol.
在成年哮喘患者中，选择性β2肾上腺素能激动剂沙美特罗具有持久的支气管扩张和支气管保护作用。迄今为止，关于沙美特罗在儿童中的已发表研究很少。
在一项针对20名儿童的随机、双盲、患者内四向交叉单剂量研究中，我们通过定量吸入器比较了25微克和50微克沙美特罗、200微克沙丁胺醇以及安慰剂的支气管扩张和支气管保护作用。
在4个研究日，平均基线第1秒用力呼气量（FEV1）和乙酰甲胆碱激发试验的PC20无显著差异（p>0.05），安慰剂给药后也无显著变化。与安慰剂相比，沙丁胺醇给药后5至30分钟FEV1显著增加，25微克或50微克沙美特罗给药后5分钟至12小时FEV1显著增加。25微克或50微克沙美特罗给药后，5分钟和10分钟时FEV1显著低于沙丁胺醇给药后，30分钟时与沙丁胺醇无差异，3至12小时时显著高于沙丁胺醇给药后。25微克沙美特罗和50微克沙美特罗对FEV1的作用无显著差异。沙丁胺醇给药后，仅在30分钟时PC20有显著增加。25微克或50微克沙美特罗给药后，PC20从30分钟至12小时显著增加。25微克和50微克沙美特罗分别在3至12小时和30分钟至12小时提供了比沙丁胺醇显著更强的支气管保护作用。50微克沙美特罗在30分钟至12小时提供了比25微克沙美特罗显著更好的支气管保护作用。FEV1变化引起的PC20变化量在14%至28%之间，表明对支气管收缩的保护并不完全依赖于支气管扩张。
沙美特罗是一种强效、长效支气管扩张剂，支气管扩张起效比沙丁胺醇慢。它提供了比沙丁胺醇显著更强且更持久的支气管收缩保护作用。
