Fig. 5. Salicylate flux (right axis) and differential signal (left axis) in three segments of the Malpighian tubule, and in the midgut, the ileum and the rectum. The height of each bar is the mean ±S.E.M. for the number of sites indicated at the bottom of each bar. The number of different preparations is indicated in brackets. At each site, the salicylate flux was calculated as the mean of five replicate measurements.