Table 1.
Effect of formoterol, given intranasally an hour before the allergen challenge, on allergen-induced increase in Penh, airway space cellular infiltration and increased airway sensitivity to aerosolized methacholine
| Allergen-induced increase in Penh (times increase) | BAL eosinophils (105 cells ml−1) | BAL neutrophils (105 cells ml−1) | BAL macrophages (105 cells ml−1) | BAL lymphocytes (105 cells ml−1) | PC200 (mM) | |
|---|---|---|---|---|---|---|
| PBS/PBS | 0.94±0.02* | 0.01±0.01* | 0.01±0.01* | 0.58±0.09* | 0.01±0.01* | 89.2±6.4* |
| OA/PBS | 0.98±0.03* | 3.09±0.47* | 0.08±0.04* | 2.28±0.71* | 0.86±0.09* | 63.3±9.4* |
| OA/OA | 2.70±0.21 | 9.57±0.58 | 0.60±0.16 | 3.17±0.42 | 2.01±0.22 | 42.5±10.1 |
| Formoterol | ||||||
| 1.5 μg kg−1 | 2.50±0.25 | 6.90±1.07 | 1.55±0.14* | 2.52±0.25 | 1.42±0.18 | 50.1±14.3 |
| 5 μg kg−1 | 3.32±0.56 | 7.66±1.15 | 1.62±0.45* | 2.21±0.25 | 1.29±0.18* | 44.3±12.9 |
| 15 μg kg−1 | 3.11±0.50 | 7.32±1.67 | 0.78±0.15 | 3.27±0.63 | 1.24±0.5* | 48.4±16.2 |
| 50 μg kg−1 | 2.38±0.41 | 6.43±0.54* | 0.53±0.10 | 1.54±0.20* | 1.11±0.24* | 24.5±4.2 |
| 150 μg kg−1 | 3.67±0.30 | 6.31±0.56* | 0.39±0.07 | 1.83±0.17* | 1.34±0.14* | 14.2±3.1* |
Abbreviations: BAL, bronchoalveolar lavage; OA, ovalbumin; PBS, phosphate-buffered saline; PC200, concentration of methacholine that produced a 200% increase above baseline of the Penh value.
Actively sensitized animals were challenged with aerosolized OA or its vehicle PBS on days 21–23 after the first sensitization. On day 26, mice were either challenged with an aerosolized solution of OA (OA/OA) or PBS (OA/PBS). As a control, a group of sensitized animals was challenged with PBS on days 21–23 and 26 (PBS/PBS). Results are expressed as means±s.e.mean from one experiment with 7–8 animals per group. Statistical comparisons were performed using a Mann–Whitney test with Bonferroni correction for multiple comparisons.
P<0.05 when compared with the OA/OA group.