Figure 7. Developmental changes.

A, train stimulation-induced disinhibition was tested in 2- and 3-week-old mice in control (n = 8, n = 10, respectively) and in the presence of 0.5 μm CGP-55845A (n = 8, n = 8, respectively). See Fig. 3A–C for statistical significance. B, left panel, amplitude plot showing the effect of the GABA_BR agonist baclofen (10 μm) on mIPSCs recorded from a stellate cell at a holding potential of −35 mV in a P14 mouse. Example traces represent recording in the absence (1) and in the presence (2) of baclofen. Right panel, summary data showing the reduction of mIPSCs frequency upon superfusion of 10 μm baclofen in 2- and 3-week-old mice (white bars, n = 5, n = 6, respectively). In 2-week-old mice, 2 μm CGP-55845A was needed to completely abolish the baclofen effect (black bars, 0.5 μm CGP: n = 4, 2 μm CGP: n = 5). See Fig. 2C for statistical significance. C, left panel, example recordings showing the effect on GAT-1 blockade (N0–711, 5 μm) on pharmacologically isolated eIPSCs evoked by a train stimulation (5 stimuli, 50 Hz) in the molecular layer of a P14 mouse. Average responses in NO-711 (grey) were normalized to control responses (black) relative to the fifth peak. Right panel, percentage tail current relative to peak amplitude was estimated at 100 ms after eIPSC onset in control (white bars) and in the presence of NO-711 (grey bars) in 2- and 3-week-old-mice (n = 6 for both age groups). Asterisks indicate statistical significance tested with paired Student's t test.