Asynchronous synaptic responses in hippocampal CA1 neurons during synaptic long-term potentiation.

In guinea pig hippocampal slices incubated in Ba2+, stimulation of stratum radiatum induced an EPSP that was followed by an increased frequency of miniature EPSPs in CA1 neurons. These miniature EPSPS, which were presumably due to the asynchronous release of transmitter, were increased after the induction of long-term potentiation.