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Recent studies have revealed the existence of several types of coherent network oscillatory activity in the various nuclei of basal ganglia.The oscillatory activity is believed to play an important function in both the normal physiology and pathophysiology of this system, but little is known about its mechanisms.Intrinsic resonance properties of the neurons possibly provide a basis for the oscillations.So, we studied the resonance characteristics of globus pallidus (GP) neurons and their ionic mechanisms using whole-cell patch-clamp recordings in rat brain slices.A swept-sine-wave current with constant amplitude and linearly increasing frequency (0-18 Hz for 20s) was applied to measure the resonance frequency of GP neurons.We found that the resonance occurs in type A neurons of GP (GP A) and was temperature and voltage-dependent.Type B and C neurons of GP had no significant membrane resonance.The resonance frequency of GP A neurons was about 3 Hz when temperature was maintained at 34℃ and holding potential was at-70 mV.The resonance frequency increased with more negative holding potentials and decreased with lower temperature.When large-amplitude ZAP current was injected, action potentials fired most readily as the input frequencies near resonance frequency.After application of ZD7288 (20μM), the resonance of Type A neurons was blocked and the spikes arose readily at the lowest frequencies, indicating that hyperpolarization-activated cation current generated the resonance and facilitated the frequency preference of the neurons.In conclusion, there is a resonance mediated by hyperpolarization-activated cation current in individual GP A neurons.The resonance may participate in normal physiology and pathophysiology of basal ganglia.