Depression biased non-Hebbian spike-timing-dependent synaptic plasticity in the rat subiculum

摘要: The subiculum is a structure that forms bridge between the hippocampus and entorhinal cortex (EC), plays major role in memory consolidation process. Here, we demonstrate spike-timing-dependent plasticity (STDP) at proximal excitatory inputs on subicular pyramidal neurons of juvenile rat. Causal (positive) pairing single EPSP with back-propagating action potential (bAP) after time interval 10 ms (+10 ms) failed to induce plasticity. However, increasing number bAPs burst three, two different frequencies 50 Hz (bAP burst) 150 Hz, induced long-term depression (LTD) +10 both regular-firing (RF), weak firing (WBF) neurons. LTD amplitude decreased bAP burst. Reversing order LTP -10 ms. This finding contrast reports other synapses, wherein prebefore postsynaptic (causal) vice versa. Our results reaffirm earlier observations relative timing pre- activities can lead multiple types profiles. induction timing-dependent (t-LTD) was dependent calcium change via NMDA receptors WBF neurons, while it independent change, but required active L-type channels RF Thus mechanism synaptic may vary within hippocampal subfield depending neuron involved. study also novel induction, where are involved presynaptically findings have strong implications process owing central this