{"title":"Bronchodilating effects of bambuterol on bronchoconstriction in guinea pigs.","authors":"Q M Xie, L H Zeng, Y X Zheng, Y B Lu, Q H Yang","doi":"","DOIUrl":null,"url":null,"abstract":"<p><strong>Aim: </strong>To study the effects of bambuterol (Bam) on bronchoconstriction in guinea pigs.</p><p><strong>Methods: </strong>Bronchospasm induced by histamine aerosol, lung resistance (RL) and dynamic lung compliance (Cdyn) changes induced by ovalbumin aerosol in vivo, isolated resting lung parenchyma strips, and carbamylcholine-induced tracheal constriction in vitro in guinea pig were investigated.</p><p><strong>Results: </strong>Bam dose-dependently prolonged the time to histamine-induced collapse, ED50 values (95% confidence limits) of Bam intragastric gavage (i.g.) after 1 h, 4 h, and 24 h were 0.74 (0.60-0.91), 0.75 (0.61-0.91) and 1.00 (0.77-1.30) mg.kg-1, respectively. Bam 2 or 10 mg.kg-1 i.g. 2 h before ovalbumin aerosol partly or almost completely inhibited bronchial challenge of ovalbumin-induced change of RL and Cdyn. Bam 0.1-1.0 mumol.L-1 gave a weak relaxation on isolated tracheal strips induced by carbamylcholine and failed to relax the isolated resting lung parenchyma strips in guinea pig.</p><p><strong>Conclusion: </strong>Bam showed a long-acting bronchodilation by its slow metabolism in vivo.</p>","PeriodicalId":24002,"journal":{"name":"Zhongguo yao li xue bao = Acta pharmacologica Sinica","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"1999-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Zhongguo yao li xue bao = Acta pharmacologica Sinica","FirstCategoryId":"1085","ListUrlMain":"","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
Aim: To study the effects of bambuterol (Bam) on bronchoconstriction in guinea pigs.
Methods: Bronchospasm induced by histamine aerosol, lung resistance (RL) and dynamic lung compliance (Cdyn) changes induced by ovalbumin aerosol in vivo, isolated resting lung parenchyma strips, and carbamylcholine-induced tracheal constriction in vitro in guinea pig were investigated.
Results: Bam dose-dependently prolonged the time to histamine-induced collapse, ED50 values (95% confidence limits) of Bam intragastric gavage (i.g.) after 1 h, 4 h, and 24 h were 0.74 (0.60-0.91), 0.75 (0.61-0.91) and 1.00 (0.77-1.30) mg.kg-1, respectively. Bam 2 or 10 mg.kg-1 i.g. 2 h before ovalbumin aerosol partly or almost completely inhibited bronchial challenge of ovalbumin-induced change of RL and Cdyn. Bam 0.1-1.0 mumol.L-1 gave a weak relaxation on isolated tracheal strips induced by carbamylcholine and failed to relax the isolated resting lung parenchyma strips in guinea pig.
Conclusion: Bam showed a long-acting bronchodilation by its slow metabolism in vivo.