Figure 1. Inhibition of short circuit current (SCC) responses to 7,8-benzoquinoline in a Calu-3 epithelium.

SCC traces from a single Calu-3 monolayer stimulated with 7,8-benzoquinoline (250 μM, applied to both sides (bs)). Inhibitors of the current, namely acetazolamide (100 μM, bs) and bumetanide (20 μM, basolaterally (bl)), were applied sequentially (A), after which the monolayer was washed and the responses repeated, but with the order of addition of the inhibitors reversed (B). The shaded area in A represents the current removed by acetazolamide and is equal to 0.21 μequiv. The abbreviation 7,8 BQ refers to 7,8-benzoquinoline in this and other figures.