Effects of repetitive stimulation of the lateral vestibular nucleus on brain stem neurons

Abstract

Previously we showed that repetitive, high frequency stimulation of the lateral vestibular nucleus induced membrane potential oscillation in hindlimb extensor motoneurons located in the side ipsilateral to the stimulation in decerebrate rats. The frequency of the motoneuronal oscillation was nearly the same as stimulus frequencies, about 30 Hz. To know if the neuronal oscillation was generated in the brain stem, we examined unit activities of various brain stem neurons immediately after cessation of repetitive stimulation in decerebrate rats. It was found some neurons discharged spikes with a time series that had some temporal relation to stimulus pulse series even though stimulation had been terminated. We supposed motoneuronal oscillation evoked by vestibular nucleus stimulation may be in part due to brain stem mechanisms. [Jpn J Physiol 55 Suppl:S174 (2005)]