TY - JOUR T1 - Interactions between the effects of a 4-week NO<sub>2</sub> and carbon nanoparticle exposure with allergen sensitization on bronchial responsiveness in Brown Norway rat JF - European Respiratory Journal JO - Eur Respir J VL - 38 IS - Suppl 55 SP - p3855 AU - Skander Layachi AU - Françoise Rogerieux AU - Christelle Gamez AU - Kelly Blazy AU - Franck Robidel AU - Anthony Lecomte AU - Ghislaine Lacroix AU - Sam Bayat Y1 - 2011/09/01 UR - http://erj.ersjournals.com/content/38/Suppl_55/p3855.abstract N2 - Goals: The aim of this study was to assess the effect of combinations of allergen sensitization, NO2 and carbon nanoparticle (CNP) exposure on airway reactivity (AR).Methods: Brown-Norway rats were divided into the following groups: Control, CNP (FW2: Ø13nm, 0,5mg/kg) instilled intratracheally x3 at 7-day intervals, ovalbumine-sensitised (OVA), and CNP+OVA. Equal groups of animals were exposed either to air or to NO2, 10 ppm, 5h/d, 5d/wk for 4 weeks. 24h after exposure, airway resistance (Raw) was measured using forced oscillation technique (FOT) at baseline and after intravenous infusion of methacholine (MCH) (5-10 and 15 μg/kg/min (γ)). Bronchoalveolar lavage fluid (BALF) cell counts were obtained.Results: See Table 1.View this table:Table 1Conclusions: NO2 exposure and allergen sensitization caused a synergistic increase in AR. However, CNP exposure during the sensitization process decreased this effect. The observed interactions may be due to different inflammatory mechanisms induced by CNP and NO2. ER -