Cleary Jeffrey C, Karmazyn Yauel, Mogayzel Peter J, Laube Beth L
Eudowood Division of Pediatric Respiratory Sciences, The Johns Hopkins Medical Institutions, Park 316, Baltimore, MD 21287-2533, USA.
Pulm Pharmacol Ther. 2008;21(1):105-11. doi: 10.1016/j.pupt.2007.01.002. Epub 2007 Jan 25.
Acute inhalations of beta 2-adrenergic receptor agonists increase mucociliary clearance (MCC). Less is known about the effect of long-term inhalations of these agents on MCC, or cough clearance (CC). We hypothesized that chronic inhalations of nebulized levalbuterol, the R-isomer of albuterol, would enhance MCC and/or CC in healthy subjects, compared to albuterol or placebo. This was a randomized, double-blind, placebo-controlled trial in ten healthy, adult subjects who inhaled nebulized levalbuterol (1.25mg), albuterol (2.5mg), or placebo for 7 days, three times daily. MCC and CC were measured 6-7h after the last dose of drug on the 7th day of treatment. These were quantified from gamma camera images of the lungs following inhalation of an aerosol containing the isotope (99m)technetium. Levalbuterol did not improve MCC or CC. MCC averaged (+/-SD) 12.3+/-8.3%, 9.2+/-4.7% and 10.0+/-9.6% with placebo, albuterol and levalbuterol, respectively. CC averaged 3.9+/-6.8%, 4.9+/-4.3% and 3.8+/-6.4% with placebo, albuterol and levalbuterol, respectively. These results indicate that chronic inhalations of nebulized levalbuterol for 1 week do not increase MCC or CC in healthy subjects, compared to albuterol or placebo.
急性吸入β2肾上腺素能受体激动剂可增加黏液纤毛清除率（MCC）。关于长期吸入这些药物对MCC或咳嗽清除率（CC）的影响，人们了解得较少。我们假设，与沙丁胺醇或安慰剂相比，长期雾化吸入沙丁胺醇的R-异构体左沙丁胺醇可提高健康受试者的MCC和/或CC。这是一项随机、双盲、安慰剂对照试验，纳入了10名健康成年受试者，他们每天三次雾化吸入左沙丁胺醇（1.25mg）、沙丁胺醇（2.5mg）或安慰剂，持续7天。在治疗第7天最后一剂药物给药后6 - 7小时测量MCC和CC。通过吸入含有同位素（99m）锝的气雾剂后肺部的γ相机图像对其进行量化。左沙丁胺醇并未改善MCC或CC。安慰剂、沙丁胺醇和左沙丁胺醇组的MCC平均（±标准差）分别为12.3±8.3%、9.2±4.7%和10.0±9.6%。安慰剂、沙丁胺醇和左沙丁胺醇组的CC平均分别为3.9±6.8%、4.9±4.3%和3.8±6.4%。这些结果表明，与沙丁胺醇或安慰剂相比，健康受试者长期雾化吸入左沙丁胺醇1周不会增加MCC或CC。
