H+ permeability through SLC4A11 in the absence of NH3 is small.
A, baseline pHi in SLC4A11-PS120 cells (6.98 ± 0.37, n = 20) is significantly lower than in EV-PS120 cells (7.32 ± 0.41, n = 23) (independent t test, p = 0.008). B, acid recovery rates following NH4Cl pulses (see Fig. 1) in Col4 (n = 3) and Col12 (n = 3) SLC4A11-expressing cells relative to EV (n = 5). (one-way ANOVA, p = 0.001; post hoc Bonferroni EV versus Col4, p = 0.001; EV versus Col12, p = 0.012). C, pHi response to sodium acetate in EV and SLC4A11 cells. D, bar graph summary of acid load recovery rate in SLC4A11- (n = 4) or EV-PS120 (n = 4) cells during 40 mm sodium acetate pulse (independent t test, p = 0.011). Error bars, S.E. *, p < 0.05; **, p < 0.01; ***, p < 0.001.