Fig. 5. Stimulation of fluid transport by capa-1. Tubule fluid secretion was measured in the absence and presence of Drosophila capa-1 at the concentrations shown. Basal rates of secretion were measured for 30 min prior to addition of peptides. Secretion rates were measured for a further 40 min. Data are expressed as percentage stimulation of fluid secretion rate compared with basal rate (± S.E.M.; N=6–8). Statistically significant differences from basal values are denoted by asterisks, where P<0.05 determined by Student's t-test, (unpaired samples). (A) D. melanogaster; (B) A. aegypti; (C) A. stephensi; (D) G. morsitans and (E) S. gregaria.