The frequency of spontaneous GABAergic PSCs is downregulated during postnatal development. (A) Original recordings of sPSCs in NG2 glial cells of juvenile (upper trace) and adult (lower trace) mice. Recordings were performed in the presence of 10 µM NBQX, 50 µM D-APV and 5 µM CGP55845 to isolate GABAergic currents. Scale bars, 20 pA and 1 s. Gray diamonds indicate events. (B) Boxplots showing interevent interval and frequency of sPSCs for all recorded cells. The frequency was significantly lower at age p60 than at age p10 (p60: 0.0223 Hz, p10: 0.0795 Hz, p < 0.001). Thus, the interevent interval was significantly higher in adult mice than in juvenile mice (p60: 40.77 s, p10: 10.59 s, p < 0.001). (C) Recorded events (gray lines) and their average (red line) for a single NG2 cell at ages p10 (upper trace) and p60 (lower trace). Scale bars show 5 pA and 20 ms. (D) Boxplots showing peak amplitude, rise time (defined as rise time from 20% of peak amplitude to 80% of peak amplitude) and decay time (defined as the decay time constant tau). There was no significant difference between p10 and p60 for those parameters (amplitudes, p10: −7.28 pA, −9.54 pA–−6.20 pA; p60: −6.51 pA, −8.20 pA to −5.34 pA; p = 0.079; rise time, p10: 2.25 ms, 1.77–2.63 ms; p60: 2.25 ms, 1.81–2.98 ms; p = 0.45; decay time, p10: 18.93 ms, 16.15–24.58 ms; p60: 21.02 ms, 26.5–65.2 ms; p = 0.72). Mann–Whitney-U test, *** p < 0.001. p10: n = 34, N = 13; p60: n = 31, N = 11.