Simultaneous recording of presynaptic spikes and excitatory postsynaptic potentials from monosynaptically connected hippocampal neurons.

A technique has been devised to activate single granule cells in the hippocampus, and to record simultaneously spikes from the particular granule cell and excitatory postsynaptic potentials from a monosynaptically connected CA3 neuron. The unitary excitatory postsynaptic potentials (EPSPs) sustained for long observation periods, and increased in size with increases in stimulus frequency and in external Ca2+ concentration. This technique may be useful for quantal analysis of transmission through the synapse between mossy fibers and CA3 neurons.