Fig. 1.

Schematic representation of a recording of GDPs in an immature rat hippocampal CA3 neuron. a GDPs are seen as large depolarizing events among GABAergic spontaneous synaptic potentials. GDPs are GABA-mediated spontaneous pulsatile depolarizing events that occur at a frequency of 0.005–0.2 Hz. b A typical GDP rises abruptly concomitant with several action potentials, decays within 200–300 ms, and is followed by transient hyperpolarization. c Electrical stimulation at the hilus evokes a depolarizing event similar to a GDP after a stimulus intensity dependent short latency