Single pulse stimuli were delivered to the Schaffer collaterals in the in vitro hippocampal slice preparation. Local application of bicuculline to the CA3 region resulted in a series of population cell bursts in CA3, resembling the neuronal patterns which occur in the normal, freely moving rat during hippocampal sharp waves. These bicuculline-induced cell bursts in CA3 resulted in long-term potentiation (LTP) of the CA1 response. These findings suggest that the naturally occurring hippocampal sharp waves may reflect events analogous to artificially induced LTP.