Figure 6. E_Gly is influenced by voltage protocol and application interval.

Comparison of E_Gly determined in perforated-patch recordings with ‘up’ and ‘down’ protocols and various Δt values (see Methods for details). A and B, examples of glycine-evoked currents in a P2 and a P8 neurone (upper panels) and the resulting E_Gly (lower panels) obtained with an ‘up’ protocol (•), followed by a ‘down’ protocol (○), for Δt = 10 s. In the P2 neurone, E_Diff =E_Gly(up) - E_Gly(down) was 24.2 mV, whereas in the P8 neurone, E_Diff amounted to only 4.0 mV. V_s =−90 to −30 mV in A and −90 to −20 mV in B. C, group data show that E_Diff was significantly larger in P1-4 than in P8-11 neurones (14.1 ± 1.7 mV, n = 17 vs. 3.8 ± 1.8 mV, n = 12; Student's t test, P < 0.01). D, plot of E_Diff as a function of Δt demonstrates that shorter intervals increased whereas longer intervals decreased E_Diff in both P1-4 (□) and P8-11 (▪) neurones (n in parentheses). For a given Δt, E_Diff was always greater in P1-4 neurones than in P8-11 neurones.