Fig. 5. (A) Grey TIF-8 bit pictures from Ae. aegypti midguts were used for image analysis. The top midgut was treated with 10^–4 mol l^–1 MTZ and Cresol Red. The lower midgut was treated with Cresol Red in the absence of MTZ. (B) Histogram of average intensity values for treated (10^–4 mol l^–1) and untreated midgut images (from A) analyzed with ImageQuant TL software from Amersham Biosciences®. Differences were significant (P value<0.0001). 20 specimens (10 treated and 10 untreated) were analyzed in triplicate.