Fig. 2. The influence of 5-(N-methyl-N-isobutyl)-amiloride (MIA; 10^-5 mol l^-1) on intracellular pH (pHi) of gas gland cells at a constant extracellular pH (pHe) of 7.4 (A) and following an artificial intracellular acidification induced using the ammonium pulse technique (10 mmol l^-1 NH₄Cl in phosphate-buffered saline for 8 min) (B). ^*Highly significantly different from the control (P<0.01). Values are means ± S.E.M.