Figure 1.
BDNF effect on evoked PSCs. A-C, Example recordings of PSCs. The presynaptic cells were stimulated at 0.05 Hz, and each data point shows the amplitude of a PSC normalized against the average amplitude (dotted line) during the last 10 min of control period (t = -10 to 0 min). At t = 0, BDNF (100 ng/ml) was added (black line). Vh of -70 mV. Insets, Sample traces of PSCs recorded during the control period and 10-20 min after adding BDNF. A, Example of EPSCs in a glutamatergic neuron (E→E) using amphotericin B perforated whole-cell recording. B, Example of IPSCs in a glutamatergic neuron (I→E), using amphotericin B perforated recording. C, Example of IPSCs in a GABAergic neuron (I→I), using gramicidin D perforated recording. D, Summary of all experiments on BDNF effects at E→E, I→E, and I→I. Events averaged over 4 min bins and normalized to the last 10 min of the control period. Data points represent mean ± SEM. E, Scatter plot showing the extent of BDNF-induced modulation of individual synapses. Modulation factor is defined as the ratio between the mean PSC amplitude observed 15-30 min after the onset of BDNF application and the mean PSC amplitude during the control period. The average factor was 1.29 ± 0.07 at E→E (n = 12; p < 0.0001; paired t test), 0.87 ± 0.05 at I→E (n = 19; p < 0.0001), and 1.54 ± 0.07 at I→I (n = 20; p < 0.0001). For inhibitory synapses, there was no significant difference between recordings made with gramicidin D (white circles) or amphotericin B (gray circles) (p = 0.08 and p = 0.22, I→I and I→E, respectively; unpaired t test).