Mechanisms of the airway hyperresponsiveness induced by Strongyloides venezuelensis infection in rats: role of capsaicin-sensitive neurons

Strongyloides venezuelensis migrates through the lungs and induces airway hyperresponsiveness (AHR). The present study evaluated the role of C-fibers in mediating airway inflammation and AHR after infection of rats with S. venezuelensis. Neonatal treatment with capsaicin effectively depleted sensory nerves. This was accompanied by inhibition of the AHR induced by S. venezuelensis infection. In contrast, capsaicin treatment greatly enhanced pulmonary inflammation, eosinophil influx and the local production of TNF-α. In conclusion, this is the first demonstration that, akin to viral and allergic AHR, permanent loss of sensory nerve C-fibers also reduces AHR induced by infection with a helminth.