Fig. 7
Evaluation of the contribution of carbonic anhydrases and diphenylamine-2-carboxylate (DPC)-sensitive Cl− channels to carbachol (CCh)-induced pHi changes. a–c Relationships between the averaged rates of pHi decreases (−ΔpH per 10 s) versus the corresponding, averaged pHi during the pHi-decreasing phase by 10 μM CCh stimulation in the presence of 5(N,N)-dimethyl amiloride (DMA; 20 μM), and its combination with 200 μM DPC or methazolamide (Met; 1 mM). The averaged rates of pHi decreases were plotted at 10-s intervals as the pHi was decreased by CCh stimulation with the starting point indicated as CCh added. Data shown are mean ± SE (n = 7, 6, and 5, respectively). d The rates of CCh-induced decreases in pHi (−ΔpH per 10 s) at pHi of 7.27 in the presence of DMA. Simultaneous addition of either DPC or methazolamide with DMA reduced the rate (n = 7, 6, and 5, respectively). The rate at pHi of 7.27 was obtained by using linear interpolation between two data points of the means, as is indicated by an arrow, in the figure (a–c) of each condition