Pharmacological assessment of the duration of action of glycopyrrolate vs tiotropium and ipratropium in guinea-pig and human airways

摘要: 1. Our study was aimed at investigating the duration of bronchodilator action antimuscarinc drug glycopyrrolate compared to tiotropium and ipratropium. In guinea-pig isolated trachea, time (t1/2) necessary for a contractile response carbachol (0.3 microM) return 50% recovery after washout antagonist studied. The offset effect glycopyrrolate, ipratropium (10 nM each) t1/2 = 4.0 +/- 0.5, > 4.5 0.5 0.1 h, respectively. At h from antagonist, 50 8, 10 4 70 7%, 2. human bronchus, effects (3 nM), (1 nM) 3.7 0.2; 6 3.0 0.2 6.0 101 10, 27 3 110 10%, 4. anaesthetized guinea-pigs, acetylcholine-induced bronchoconstriction markedly reduced by intratracheal instillation nmol kg(-1); 88.1 4% inhibition), (1.3 86.2 5% inhibition) or (1.45 10% inhibition). These inhibitory assessed 24 administration were 69.9 5 29.7 6%; 28.3 14.2 ipratropium, respectively, whereas they remained stable (83.5 4; 70.6 6) tiotropium. residual also 16 administration, proved be as low that found (31.2 vs 6%, respectively). 5. conclusion, glycopyrrolate-induced bronchodilation has longer than but less efficacy possible glycopyrrolate-based therapy asthma chronic obstructive pulmonary disease given once-a-day is not guaranteed present investigation.