Abstract
We evaluated the effects of intermittent (96 hrs of interval - IS) and diary (DS) salbutamol treatments in ovalbumin (OVA) induced chronic inflammation model. METHODS: Balb/c mice were sensitized with i.p. 50µg OVA+ 6mg Al(OH)3 at day 0 and boostered at days 12, 32 and 46. Starting at day 24, the animals were challenged with aerossol of 1% OVA on alternate days until day 58. Salbutamol treatment started at day 34 until last OVA inhalation. Forty-eight hours after last OVA challenge, mice were anesthetized with sodium pentobarbital (70mg/kg) and bronchoalveolar lavage (BAL) was performed. The number of eosinophils (EPO+ cells) and lymphomononuclear cells (LMN) was evaluated in the airways and lung parenchyma. RESULTS: OVA mice present an increase in total cells, neutrophils and eosinophils in the BAL compared to controls (7.5 vs. 0.9, 1.6 vs. 0.7, and 2.5 vs. 1.4; x105cells/mL, p<0.05). There was also an increase in LMN and EPO+ cells in the peribronchial wall. Salbutamol exposure reduced neutrophils in both IS and DS groups (p<0.05) and eosinophils (only DS group, p<0.05). Peribronchial EPO+ cells were also reduced in IS compared to OVA (1.9 vs 4.2 cells/104µm², p<0.001). EPO+ cells were reduced in lung parenchyma in both IS and DS compared to OVA (1.4 and 1.9 vs 3.2 cells/104µm², p<0.05). No reductions in LMN were observed in the airways. CONCLUSION: Our data suggest that, in this murine experimental model of chronic allergic pulmonary inflammation, salbutamol treatment attenuates airway and alveolar inflammation. Supported by CAPES, FAPESP and CNPq.