Figure 3
Muscarine-induced reductions in luminal area of peripheral bronchi from FVB mice. (A) Luminal area of peripheral bronchi after application of 10-6 M muscarine (Mus) as recorded by videomorphometry. Data (means ± S.E.M) were expressed as % luminal area. Bronchi from FVB mice (4 slices from 6 lungs) responded to 10-6 M muscarine until wash out (Wash). Time points 1–4 were chosen as indicators for initial and sustained constriction. 1 = luminal airway area 1 min after muscarine application, 2 = luminal airway area 15 min after muscarine application, 3 = luminal airway area 1 min after repeated muscarine application, 4 = luminal airway area 15 min after repeated muscarine application. Effect of DHS (B) and DMS (C) on muscarine-mediated reductions in luminal area of peripheral bronchi from FVB mice. The luminal area of peripheral bronchi (expressed in %) was recorded by videomorphometry after application of 10-6 M muscarine (Mus) alone and after application of 10-6 M muscarine together with (B) 10-6 M DHS (diamonds, 7 slices from 4 lungs) and 10-10 M DHS (triangles, 8 slices from 4 lungs) or (C) 10-6 M DMS (diamonds, 9 slices from 7 lungs) and 10-10 M DMS (triangles, 6 slices from 4 lungs). Bronchoconstriction responses were significantly reduced in the presence of DHS and DMS. The inhibition was more pronounced following coadministration of DMS. Data are given as means ± S.E.M.