Fig. 6. Time course of recovery from inactivation. (A) Inward currents recorded using a double pulse protocol in which a 20 ms control pulse from –84 to –24 mV was followed by a second identical voltage pulse. (B) The plots show the recovery time course of the Na⁺ currents. The curves represent the fits of a single exponential function, giving values of time constants of 9.6 ±1.2 ms (N=5) for perforated mode (filled circles), 13.1±0.7 ms (N=5) in conventional mode (open circles) and 16.5±2.4 ms (N=5) for the condition containing 0.5 mmol l^–1 GTPS in the internal solution (open triangles).