Bronchoconstriction of the asthmatic airway by inhaled and ingested propranolol.

摘要: Responsiveness to inhaled histamine and DL propranolol hydrochloride was measured in 31 adult asthmatics compared with bronchoconstriction provoked by acute oral dosing (max 160 mg). Twelve developed greater than or equal 15% reduction the forced expired volume 1 s (FEV1), 2 h after less 100 mg propranolol; cardiac beta-adrenoceptor blockade confirmed cycle exercise tests 19 without airway response. The provocative dose of each aerosol causing a 20% fall FEV1 (PC20) lower, 0.43 mg.ml-1, 3.12 12 positive test negative test, PC20 1.65 16.2 mg.ml-1 (P 0.001 for both aerosols). A correlation demonstrated between values (r = 0.72, P 0.001, n 19) but not remainder 0.14, 0.05, 12). Plasma concentrations (CL, ng.ml-1) final did correlate % delta (26.3) -0.28) when an response tachycardia (25.9%) 0.31) no occurred. CL exceeded limit detection (7.5 weakly related value 0.53, 0.01, 27). prevalence challenge low this group (39%).(ABSTRACT TRUNCATED AT 250 WORDS)