Fig. 2.

The delayed current transient is abolished by bicuculline and by Cd²⁺. A, Two series of five representative current responses to depolarizing somatic voltage pulses (test potential, −30 mV; pulse duration, 0.8 msec; pulse frequency, 0.67 Hz), one obtained shortly after breaking into the whole-cell recording mode (black traces), and the other obtained after 7 min of whole-cell recording (gray traces). B, Decay of the peak amplitude of delayed inward current transients as a function of time in whole-cell recording, from the same cell as in A. Six points deviate strongly from the main decay curve: they correspond to traces that were contaminated with a spontaneous IPSC. C, In another cell, responses to depolarizing somatic voltage pulses (test potential, −30 mV; pulse duration, 1 msec; pulse frequency, 0.67 Hz), shortly after breaking into the whole-cell recording mode (black traces), and after 7 min of whole-cell recording (gray traces), in the presence of bicuculline. D, Plot of the peak amplitude of delayed inward current transients as a function of time, from the same cell as in C. E, F, Same experiment as in C and D, except that the current was here challenged by a solution containing 50 μmCd²⁺.