Standard electrophysiology was performed as described by Vierbuchen et al. [57] and Pang et al. [58]. Spontaneous post-synaptic currents (PSCs) were obtained from neurons with the resting membrane potential held at −70 mV. Both current and voltage clamp experiments were performed. For step current experiments, membrane current was held at 0 pA. 5 pA current injections were provided from −20 pA to 35 pA. In voltage clamp experiments, resting membrane voltage was held to -60mV. Step voltage injections were given from −100 mV to 0 mV with a step size of 10 mV. Action potentials and synaptic currents were monitored with Multiclamp 700B amplifier (Molecular Devices). Clampex 10 data acquisition software (Molecular devices) was used for collecting data. The whole-cell pipette solution contains (in mM) 126 K-Gluconate, 4 KCl, 10 HEPES, 0.3 Na2-GTP, 4 Mg-ATP and 10 Phosphocreatine (pH 7.2, adjusted with KOH). The bath solution contains (in mM) 140 NaCl, 5 KCl, 2 MgCl2, 2 CaCl2, 10 HEPES, 10 glucose (pH 7.4, adjusted with NaOH).
