Fast synchronous oscillations of firing rate in cultured rat suprachiasmatic nucleus neurons: Possible role in circadian synchronization in the intact nucleus

► Electrical activity of dispersed and cultured SCN neurons in MED was studied ► At 20-s averaging fast oscillations of firing rate with period ∼30 min were revealed ► Synchronous fast oscillations of firing rate among different cells were revealed ► Synchronous circadian peaks among many cells in distant parts of MED were revealed ► Transition of arrhythmic activity to circadian pattern accompanied fast oscillations.