Figure 1.

Bath application of DA, but not ISO restores hippocampal spike-timing dependent plasticity in sucrose prepared slices. (A) Synaptic responses were recorded in the current clamp mode in CA1 pyramidal neurons of juvenile rats (P15–P20). Pre-stimulus membrane potential prior to recording was −70 mV for all cells. Presynaptic stimulation of Schaffer collaterals was performed every 20 s (for graphs: data binned to 1 min means). After recording of baseline for 10 min, STDP was induced by a 1EPSP/1AP pairing (100×, every 2 s; at time point zero). Black symbols indicate neurons of the DA depleted group (DA depletion), red symbols indicate DA treated neurons (+20 μM DA) and blue symbols show ISO treatment (+10 μM ISO; ^*p < 0.05). Inset on the left side shows original traces before and after STDP induction for the three different conditions. (B) AP rise times for all three conditions. Rise time is significantly faster after application of the neuromodulators. (C) Modulation of spike latency by neuromodulators: latency to first spike for DA depletion (black), rescue by DA (red) and unsuccessful rescue by ISO (blue).