Understanding the intrinsic membrane properties of juxtaglomerular (JG) cells is a necessary step toward understanding the neural basis of olfactory signal processing within the glomeruli. We have used patch-clamp recordings, two-photon Ca²⁺ imaging in rat olfactory bulb slices to investigate mechanisms for generating a long-lasting plateau potential and characterize its functional input/output roles in the glomerular network. Plateau potentials of JG cells were initially generated by dendritic calcium channels. Bath application of Ni²⁺ (250 µM to 1 mM) totally blocked the plateau potential. A local puff of Ni²⁺ on JG cell dendrites, but not on the soma, blocked the plateau potentials, indicating the critical contribution of dendritic Ca²⁺ channels. Imaging studies with two-photon microscopy showed that a dendritic Ca²⁺ increase was always correlated with a dendritic but not somatic plateau potential. The dendritic Ca²⁺ conductance contributed to boosting the initial EPSPs to produce a plateau potential which shunted and reduced the amplitudes of the following EPSPs. This enables those JG cells to act as low-pass filters to convert high frequency inputs to low frequency outputs. The low frequency (2.6 ± 0.8 Hz) of rhythmic plateau potentials appeared to be determined by the intrinsic membrane properties of the JG cell. These properties of the plateau potential may enable JG cells to serve as pacemaker neurons in the synchronization and oscillation of the glomerular network.