Reverberatory activity has been theoretically considered as neural process underlying short term memory.Dopamine input can regulate aspects of neural activity associated with learning and memory,but its precise effects on network reverberation are still unclear.We have shown previously that small networks of cultured hippocampal neurons could elicit rhythmic persistent activity following a single brief stimulus,and thus could be used as an in vitro model system to study network reverberation.Here we investigated the effect of dopamine on reverberation in these small networks.We found that dopamine(1~100uM)could reduce the occurrence of reverberation in a dose-dependent way with higher concentration of dopamine suppressing more.This suppression was not affected in the presence of GABAA receptor antagonist bicuculline.Furthermore,dopaminergic inhibition of reverberation was completely rescued by D2-like receptor antagonist sulpiride,suggesting that dopaminergic regulation may act through a D2-like receptor mediated pathway.