The delayed current transient is blocked by intracellular BAPTA. A, Mean delayed current transient (6 consecutive traces each; stimulation frequency, 0.25 Hz) recorded shortly after break-in (labeled 30 s) and after approximately 8 min of whole-cell recording. The pipette solution contained 10 mm BAPTA instead of the usual 1 mmEGTA. B, Time course of decay of the peak amplitude; series resistance during recording, 24 MΩ. C, D, Summary results for six control cells and six BAPTA-dialyzed cells, showing values (mean ± SEM) for the maximum peak delayed current transient (obtained during the first minutes of whole-cell recording) and for the time to half decay of this current. Average series resistance values were 24 ± 5 MΩ for the control cells and 36 ± 6 MΩ for the BAPTA-dialyzed cells.