RT Journal Article SR Electronic T1 Studying human airway pharmacology in microsections: application of videomicrometry JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP 991 OP 996 DO 10.1183/09031936.02.00942001 VO 19 IS 6 A1 Schmidt, D.T. A1 Dent, G. A1 Rühlmann, E. A1 Muñoz, N.M. A1 Leff, A.R. A1 Rabe, K.F. YR 2002 UL http://erj.ersjournals.com/content/19/6/991.abstract AB The influence of endogenously-released mediators and activated eosinophils on the airway lumen and the effect of passive sensitization on anti-immunoglobulin (Ig)-E-induced contractile responses was investigated by videomicrometry. Human bronchial sections of 2–3 mm internal diameter, placed in 250 µL Hank's balanced salt solution on microtitre plates, were monitored and recorded by digitized image analysis. Airway preparations exhibited a spontaneous narrowing (mean±sem −33±5% of the luminal area). Removal of the bronchial epithelium almost completely prevented the development of spontaneuous narrowing (−6±3%; p<0.001). The addition of platelet-activating factor stimulated human eosinophils to the bronchial sections led to significant narrowing of the airway lumen (−39±9%; p<0.05). Passive sensitization induced hyperresponsiveness to polyclonal anti-IgE (−35±8%; p<0.01). It is concluded that videomicrometry is suitable for studying interactions between human airways and inflammatory cells, as well as the effect of passive sensitization on smooth muscle reactivity in vitro, without the imposition of preload. Under these conditions, human airways exhibited a spontaneous decrease of the airway lumen over time suggesting a role for epithelium-derived mediators because the development of spontaneous tone was epithelium dependent. This work was funded by grants from the German Ministry for Research and Technology (BMFT 01 KE 9301) and the National Institutes of Health (HL-46368, SCOR HL-56399, NIAID V01-AI-34566).