vertical gravity puller (Narishage International USA, East Meadow, NY) to a final pipette resistance of 3–5 MΩ. Neurons were patched with pipettes containing an internal solution containing (in mM): potassium-D-gluconate, 140; sodium chloride, 4; magnesium chloride, 2; EGTA, 1.1; HEPES, 5; Na2ATP, 2; sodium creatine phosphate, 5; Na3GTP, 0.6. Neurons were chosen at random for patch-clamp recording and analyzed for evoked activity in current-clamp as shown in Fig. 3. For voltage-clamp recordings, voltage-steps from −100 mV to +70 mV were used to elicit voltage-gated Na+ currents and K+ currents.
