(9R)-9-chloro-11-17-dihydroxy-17-(2-hydroxy-1-oxoethyl)-10-13-16-trimethyl-6-7-8-11-12-14-15-16-octahydrocyclopenta[a]phenanthren-3-one and Hyperventilation

The aim of this study was to assess whether a single high dose of beclomethasone dipropionate (BDP) could blunt mast cell activation and bronchoconstriction after eucapnic voluntary hyperpnea (EVH).. In this model of exercise-induced bronchoconstriction (EIB), seven athletes with EIB and eight untrained subjects with mild asthma performed two EVH tests 5.5 h apart on the same day; the first challenge after inhalation of a placebo aerosol and the second 4 h after inhalation of BDP (1500 microg). Prechallenge and postchallenge pulmonary function and urinary excretion of the mast cell mediator 9alpha, 11beta-prostaglandin (PG) F2 were followed, as well as urinary excretion of the bronchoconstrictor leukotriene (LT) E4.. The EVH-induced bronchoconstriction was inhibited by BDP in both groups (P < 0.001): in athletes, mean +/- SEM percent fall in forced expiratory volume in 1 s was 22% +/- 4% after placebo versus 13% +/- 3% after BDP; in subjects with asthma, 23% +/- 4% after placebo versus 14 +/- 3% after BDP. This inhibition of airway response was associated with a significant reduction in the urinary excretion of 9alpha,11beta-PGF2 (P = 0.039) and LTE4 (P = 0.003) in both groups. Significant correlations were found between the percent fall in forced expiratory volume in 1 s and the increase in urinary excretion of both mediators 9alpha,11beta-PGF2 (r = 0.544, P = 0.002) and LTE4 (r = 0.380, P = 0.038) after EVH.. We conclude that a single dose of BDP has an acute protective effect on the bronchial response to hyperpnea in both untrained subjects with asthma and athletes with EIB. This effect was associated with decreased excretion of urinary mediators, suggesting that BDP blunted the mast cell activation.

Topics: Administration, Inhalation; Adult; Anti-Inflammatory Agents; Asthma, Exercise-Induced; Beclomethasone; Dose-Response Relationship, Drug; Female; Humans; Hyperventilation; Male; Mast Cells; Young Adult

To investigate whether inhaled steroids modulate the airway response to different bronchoconstrictive stimuli, we studied 25 subjects with mild asthma with a double-blind, noncrossover design to compare the effect of a 3-week treatment with salbutamol (0.2 mg, four times a day [q.i.d.]) and placebo (N = 11) to the effect of salbutamol (0.2 mg q.i.d.) and inhaled beclomethasone dipropionate (BDP, 0.5 mg q.i.d.) (N = 14). Airway response to histamine and methacholine was assessed as the provocative concentration (in milligrams per milliliter) necessary to increase the specific airway resistance (SRaw) (in centimeters of H2O times second) by 100% (PC100 SRaw). Airway response to hyperventilation of air and to hyperventilation of 0.75 ppm of sulfur dioxide (SO2) was determined as the provocative ventilation (in liters per minute) necessary to increase SRaw by 75% (PV75 SRaw). Challenges were performed on separate days before and after treatment, and salbutamol inhalation was withheld at least 6 hours before each challenge. Salbutamol and placebo did not change perchallenge baseline SRaw nor did they have any significant effect on the airway response to the stimuli. Salbutamol and BDP decreased the mean prechallenge baseline SRaw (SEM) from 7.7 (0.37) to 5.9 (0.28) (p less than 0.01) and significantly (p less than 0.01) increased geometric mean (SEM) PC100 SRaw for histamine from 0.5 (1.42) to 0.9 (1.53) mg/ml; for methacholine, from 0.2 (1.47) to 0.5 (1.51) mg/ml; and mean (SEM) PV75 SRaw for hyperventilation of air from 51.8 (2.32) to 58.4 (1.86) L/min. In contrast, the change of PV75 SRaw during hyperventilation of SO2 from 26.2 (2.29) to 31.4 (3.30) L/min was not significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Administration, Inhalation; Adrenal Cortex Hormones; Airway Resistance; Albuterol; Asthma; Beclomethasone; Bronchi; Bronchial Provocation Tests; Histamine; Humans; Hyperventilation; Methacholine Chloride; Sulfur Dioxide