Fig 6.

Effect of tiotropium on capsaicin-induced bronchospasm and firing of airway-specific sensory afferent nerves. A, Example of recording of bronchospasm (top trace) and simultaneous vagus nerve single C-fiber firing (bottom trace). Capsaicin (100 μmol/L) was administered by means of aerosol for 15 seconds and indicated by arrows below the traces. Saline (0.9% for 1 minute) and tiotropium (100 μg/mL for 1 minute) administration are indicated below the traces by arrows. Voltage and pressure scales are indicated by bars on the left of the traces, and the time scale is provided by a 60-second black bar between the traces. B-D, Histograms represent the average changes in airway pressure induced by capsaicin before and after tiotropium (Fig 6, B), the average peak frequency of impulses per second recorded from vagus nerve single C-fiber capsaicin-induced firing before and after tiotropium (Fig 6, C), and the average total impulse count over time (5-minute window from nebulization) recorded from vagus nerve single C-fiber capsaicin-induced firing before and after tiotropium (Fig 6, D). Data are shown as means ± SEMs (n = 3). *P < .05 and **P < .01 as determined by Mann-Whitney U test.