In Vivo Plasticity at Hippocampal Schaffer Collateral-CA1 Synapses: Replicability of the LTP Response and Pharmacology in the Long-Evans Rat

Figure 3

Differential synaptic LTP response induced by the 40/40 and 50/50 HFS protocols in LE rats. (a) Average input/output curves between stimulation voltage and fEPSP slope overlap and show no significant difference in basal synaptic excitability. (b) fEPSPs were enhanced compared to baseline following 40/40 HFS (black, ) and 50/50 HFS (green, ) to a similar level. LTP induced by HFS was high throughout the whole 2-hour posttetanisation; however, there was no significant difference between the LTP response induced by both 40/40 and 50/50 HFS protocols. Data are presented as . Outsets above LTP curves represent average waveform field potentials during 30 min baseline prior to tetanisation and 0-30 min and 90-120 min posttetanisation. Horizontal bar: 1 mV; vertical bar: 5 ms. (c) PTP, STP, and LTP responses are presented as .

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