Fig. 9.

Functional Kv7 channels are required for maintaining resting diameter of small airways in human lung slices. A: representative images of a small airway before treatment (control), in the presence of 50 nM histamine applied for 5 min (50 nM Hist), in the presence of 50 nM histamine applied with 100 μM flupirtine for 5 min (50 nM Hist + 100 μM F), following a 10-min washout of histamine and flupirtine (washout), and in the presence of 10 μM XE991 applied for 10 min. B: corresponding representative time course of changes in luminal area of the same small airway. Both 50 nM histamine (Hist) and 50 nM histamine with 100 μM flupirtine (Hist + F) were applied for 5 min followed by a 10-min washout in each case; 10 μM XE991 was applied for 10 min. C: summarized bar graph of average airway luminal area measured in multiple lung slices from 2 human subjects. Luminal area measured during the last min of treatment with 50 nM histamine (Hist), 50 nM histamine with 100 μM flupirtine (Hist + F), or 10 μM XE991 was normalized to control area measured before treatments; *significant difference from control (1-way ANOVA, P < 0.001, n = 6–8); #significant difference between histamine alone and histamine plus flupirtine treatment groups (paired Student's t-test, P < 0.05, n = 6).