Allergen-Induced Bronchoconstriction in Asthmatic Children (6)
The total WBC, neutrophil, and eosinophil counts were checked before challenge and at 5 and 10 minutes after the completion of PAF challenges. Symptoms such as throat irritation, cough, flushing, dyspnea, and tachycardia were recorded during the test and within the 24 h after challenge. antibiotics levaquin
Data were expressed as mean ± SD and were analyzed by paired Students t test. A p value of <0.05 was considered significant.
As shown in Table 1, the four studied groups were comparable regarding the age and baseline FEV,. The asthmatic patients had a much smaller methacholine PD20 than did controls, but no difference was found among the three asthmatic groups.
The protective effect, as measured by changes in FEV,, of aerosol BN52021 on PAF-induced bronchoconstriction in normal individuals and asthmatic children is shown in Figure 1. BN52021 itself had no effect on the baseline FEV,. Although six of the seven asthmatics showed a greater than 20 percent decrease in FEV, after inhaling the highest dose of PAF (1,000 mg/L), only one of the seven normal subjects showed a greater than 20 percent decrease in FEV,. Prior inhalation of BN52021 was able to inhibit the bron-choconstrictive effect of PAF in both normal subjects (Fig 1A) and asthmatics (Fig 1B).
Figure 1. Platelet-activating factor (PAF) challenge tests. Each subject inhaled either placebo or BN52021 in a doubleblind, crossover fashion, and then performed PAF challenge by standard provocation protocol. The decrease of FEV, (mean ± SD) was much greater in asthmatics than in normal subjects at each concentration of PAF studied. Six of seven asthmatics and one of seven normal subjects gave a positive response to PAF challenge. Furthermore, BN52021 inhibited PAF-induced bronchoconstriction in a dose-dependent manner. Error bars were omitted for clarity.