Fig. 6.

The effect of protein kinase A inhibitor H-89 (10 μM) and ouabain (1 μM) on the rate of cytoplasmic pH recovery after ammonium chloride removal. H-89 was introduced after establishment of a steady baseline pH but before the addition of ammonium chloride. Ouabain was added 5 min after H-89. H-89 and ouabain were present throughout the rest of the experiment. Values are means ± SE of results from 10–37 independent experiments. *P < 0.05, **P < 0.01, ***P < 0.001, significant difference from control. ###P < 0.001, significant difference from 1 μM ouabain.