Subsequently, the maximal treadmill exercise test was repeated to evaluate aerobic performance. The non-aerobically trained groups (Control and OVA) were not submitted to the AE protocol and were instead adapted to the treadmill for 3 days per week (8% inclination, 0.3 km/h, 5 min per session) until the last treadmill exercise test. Forty-eight hours after the last session of training and OVA or saline inhalation, all animals were anesthetized with sodium thiopental (170 mg/kg, i.p.), tracheostomized, and mechanically ventilated (60 breaths/min; 6 ml/kg of tidal volume)
with a mechanical ventilator for small animals selleck chemicals llc (Harvard, Rodent Ventilator Model 683, MA, USA) (Prado et al., 2005). Next, a sample of exhaled air was collected in a Mylar bag at the expiratory output valve for 5 min (Mehta et al., 1998 and Ramos et al., 2010). ENO was MAPK Inhibitor Library screening measured by chemiluminescences using a rapidly responding analyzer (NOA 280; Sievers Instruments, CO, USA). The equipment was calibrated before each measurement with a certified 47 parts per billion (ppb) NO source (White Martins, SP, BRA). To avoid environmental contamination, a zero NO filter (Sievers Instruments) was attached to the inspiratory input. The results were expressed as parts of ENO per billion. After ENO collection, a 3-cm incision was
made in the abdomen, and blood from the inferior cava vein was collected (5 ml). The animals were then exsanguinated by cutting the abdominal aorta. A positive end-expiratory pressure of 5 cmH2O with 4% paraformaldehyde
was applied through the cannulated trachea; the anterior chest wall was removed; and the lungs were removed en bloc and immediately immersed in 4% paraformaldehyde for 24 h. Next, sections were processed with paraffin embedding, and 5-μm slices were obtained and stained with Palbociclib supplier hematoxylin and eosin for routine histological analysis and with Luna for eosinophil detection. Immunohistochemistry was also performed with anti-IL-4 (1:300), anti-IL-13 (1:150), anti-IL-2 (1:150), anti-IFN-γ (1:150), anti-IL-10 (1:50) and anti-IL-1ra (1:120) antibodies (Santa Cruz Biotechnology, Santa Cruz, CA, USA) using the biotin–streptavidin–peroxidase method ( Vieira et al., 2007 and Silva et al., 2010). The peribronchial density of eosinophils, lymphocytes, and cells positive for IL-4, IL-13, IFN-γ, IL-2, IL-10 and IL-1ra was assessed by conventional morphometry using an ocular microscope with an integrating eyepiece with 100-point and 50 lines (point-counting technique) with a known area (10,000 μm2) at 1000× magnification. Counting was performed in five non-cartilaginous airways per animal at 1000× magnification (Vieira et al., 2007). The results are expressed as cells per square millimeter.