Figure 3. PAT1-mediated inward currents induced by different substrate concentrations and varying pH_out as a function of membrane potential.

(A and B) Currents recorded at six different concentrations of glycine (1–20 mM) at extracellular pH 5.0 (A), or pH 6.5 (B) as a function of membrane potential. (C and D) Proton-dependent kinetics of glycine-induced currents determined at six different pH values ranging from pH 7.0 to pH 5.5 in the presence of either 20 mM glycine (C) or 2 mM glycine (D) as a function of membrane potential. Data are the means±S.E.M. of average currents determined in six individual oocytes. The apparent K_m and I_max values derived from these experiments are compiled in Table 1.