Figure 7From: Differentiation of neurons from neural precursors generated in floating spheres from embryonic stem cellsDifferentiated stem cells display neuronal characteristics. Currents recorded from an undifferentiated cell (A) (upper panel) in response to voltage steps to -124, -14 and 66 mV (lower panel). A representative family of currents (B) (upper panel) recorded from a cell differentiated for 20 d. Both inward Na\+(+) and outward K\+(+) currents were observed. The lower panel shows the voltage protocol with steps to (mV): -124, -24, -4, 16, 36, 56, 76. An activation curve (C) that shows the voltage generated from a Boltzmann fit to data from the cell shown in panel B (V\-(1/2) = -2.4 mV; S = 6.8 mV). Fast activating, fast inactivating inward Na\+(+) currents (D) recorded from a differentiated stem cell (upper panel). The lower panel shows the voltage protocol with a prepulse step to -104 mV followed by a family of steps to (mV) -29, -19, -14, -4. A representative family of voltage responses recorded in current-clamp mode (E) from a differentiated cell (upper panel). The lower panel shows the current protocol with steps to (pA): 0, -200, -600. In one cell we noted spontaneous action potentials in the absence of stimulation (E). All cells were held at -84 mV.Back to article page