Figure 4.

Current responses to applications of saturating GABA concentrations show different pH-sensitivity than mIPSCs. (A) Typical current responses to applications of saturating (GABA) at pH = 7.2 black) and at pH = 8 (orange) and pH = 6 (green). Traces are presented in pairs (pH = 7.2, 8.0 and pH = 7.2, 6.0) that were recorded from the same excised patches. (B) Statistics of relative amplitudes (normalized to that measured at pH = 7.2). Note a strong and monotonic pH-dependence. (C) Typical traces of mIPSCs recorded at various pH values as indicated. (D) pH-dependence of mIPSC amplitudes. Note a qualitatively different proton effect in comparison to that observed for current responses (B). Modified from Mozrzymas et al. (2003b) with permission.