Figure 2.

The spontaneous response of isolated Malpighian tubules of the yellow fever mosquito to the increase in the peritubular K⁺ concentration from 3.4 mM (A) to 34 mM (B). Numbers in red indicate statistical significant difference. Next to increasing the transepithelial secretion of K⁺, the increase in peritubular [K⁺] depolarizes the basolateral membrane voltage and increases the input conductance of principal cells as shown. For numerical detail see Hine et al^9,15 The concentrations of K⁺, Na⁺ and Cl⁻ in the hemolymph of the mosquito are respectively 6.5 mM, 96 mM and 135 mM.¹⁰