Effect of inhaled procaterol on cough receptor sensitivity to capsaicin in patients with asthma or chronic bronchitis and in normal subjects.

摘要: BACKGROUND--To evaluate the effect of inhaled beta 2 adrenergic agonists on sensitivity airway cough receptors, procaterol induced by aerosolised capsaicin, a stimulant C fibres, was studied in patients with asthma or chronic bronchitis and normal subjects. METHOD--Eleven 10 14 subjects participated. Increasing concentrations capsaicin solution were for 15 seconds tidal breathing through mouth at one minute intervals until five more coughs elicited, before 30 minutes after inhalation 20 micrograms placebo (freon gas alone) metered dose inhaler. Cough threshold defined as lowest concentration that elicited coughs. To bronchodilator bronchoconstrictor forced expiratory volume second (FEV1) measured provocation test. This test carried out both treatment placebo. RESULTS--The geometric mean value to significantly increased groups but not control The increment different between treatments each group. FEV1 all three groups. CONCLUSIONS--Inhaled has no receptor capsaicin. attenuation seen may result from tachyphylaxis