Papel e mecanismos da hiperreatividade brônquica na infecção causada por Strongyloides venezuelensis em ratos

Abstract

Alterations in lung function and pulmonary symptoms have been described in patients infected with helminthes with a lung cycle. We have previously shown that infection with the nematode Strongyloides venezuelensis induced a significant increase in airway hyperreactivity in infected rats. The aim of the present study was to test the hypothesis that bronchodilation during the lung phase of parasite migration would favor completion of the life cycle and infection indices. For this purpose, Strongyloides venezuelensis infected rats were treated with salbutamol during the first 48 h after the nematode infection. At the dose used (0.25 mg/mL for 10 min every 4 h), treatment with salbutamol preventedchanges in lung function during the parasite migration. This was accompanied by a significant increase in parasite burden, as assessed in the lung and the small intestine. We also investigated the mechanisms of airway hyperresponsiveness and observed that IL-13 does not have effect on this lung alteration. On the other hand, sensory C fibers have an important role in the airway hyperresponsiveness independent of lung inflammation