Figure 2. Electrophysiological Properties of iPS-Derived Neurons.

Whole-cell patch recordings from 12-week iPS-derived neurons from a non-alcohol dependent subject demonstrate functional neuronal properties, including generation of action potentials, spontaneous synaptic activity, and ionotropic receptor currents. (A) Neurons generate trains of action potentials in response to current injection. (B) Spontaneous synaptic activity (Inset) close-up of a spontaneous event demonstrates fast and slow kinetic components of the event. (C) GABA receptor current response to a 200 ms puff of 50μM GABA indicates that functional GABA receptors are present (arrow indicates when GABA was applied). (D) Depolarization response to a 200 ms puff of 50μM glutamate in the presence of Mg²⁺ indicates that functional AMPA receptors are expressed. Response was completely abolished when the AMPA antagonist DNQX (10µM) was perfused into the recording chamber (arrows indicate when glutamate was applied). (E) NMDA channel mediated depolarization in response to a 200 ms puff of 50μM glutamate and 10 μM glycine in a magnesium-free recording solution that contained the AMPA receptor antagonist DNQX (10µM). The response was completely abolished when NMDA receptor antagonist CPP (6µM) was perfused into the recording chamber (Dashed arrows indicate when glutamate plus glycine solution was applied).