A: Rat Hippocampal slice cultured directly on a MED probe (MED-P530A; 300μm inter-polar distance, 10 days in culture)

B: Extracellular field potentials in CA1 evoked by paired-pulse stimulation. Responses remained stable over days.

C: Comparison of the effects of various chronic treatments on synaptic responses. fEPSPs were measured in cultured hippocampal slices 3 days after different drug treatments. fEPSP amplitude was expressed as a percent of the pre-drug baseline response for each slice. Co- incubation with NMDA antagonists, such as 1μM MK801and 30μM Memantine, blocked the excitotoxic action of NMDA (10μM).