The synaptic input received by hippocampal pyramidal neurons span a wide spectrum of frequencies, including fast and slow EPSPs and IPSPs, and input from various network oscillations. Since the apical dendrites of CA1 pyramidal cells have a high h-channel density whereas M-channels are concentrated near the soma, we hypothesized that these two types of channels may differentially affect the frequency dependence of synaptic efficacy, integration, and transmission of synaptic potentials between dendrites and soma. To test these ideas, we made simultaneous whole-cell recordings from soma and apical dendrite of CA1 pyramidal cells in rat hippocampal slices. An oscillating current covering a range of frequencies (0–15Hz) was injected either into the soma or into the apical dendrite from a membrane potential of ~ ­75mV, or ~ ­50 mV and the voltage responses were recorded at both sites. At ~ ­75mV, both the soma and the dendrite displayed H-type q resonance. Although the dendrite showed significantly stronger H-resonance than the soma, their resonance frequencies were not significantly different. At ~ ­75mV, the attenuation of voltage signals along the apical dendrite was direction-dependent: propagation from soma to dendrite suffered significantly more attenuation than the opposite direction at all input frequencies tested. In contrast, at depolarized membrane potentials, the responses were dominated by M-resonance. This resonance was clearly stronger at the soma than in the dendrite. Thus, interestingly, due to the combination of dendritic h-channels, perisomatic M-channels, and passive membrane properties, these cells behave like a band-pass filter, favoring propagation of synaptic input in the q frequency range. [Supported by NFR/STORFORSK.