Fig. 7. Representative time-course of the short-circuit current (I_sc) across a distal split lamella from a posterior gill of Dilocarcinus pagei. The vertical current deflections are the responses to 4 mV voltage pulses, and are directly proportional to the transepithelial conductance (G_te, see separate scale bar). Experimental stages: 1, addition of internal ouabain (2 mol l^–1); 2, ouabain washout; 3, symmetrical addition of DMSO (0.1%); 4, external concanamycin (10 µmol l^–1); 5, internal concanamycin (10 µmol l^–1); 6, washout of DMSO and concanamycin, and internal addition of NaCN (5 mmol l^–1); 7, NaCN washout.