Olivo-cerebellar activity during harmaline-induced tremor.A 2-[14C]deoxyglucose study

The specific neuronal activity of the olivo-cerebellar system of the cat under the effect of harmaline has been studied using the 2-[14C]deoxyglucose method. The results obtained in animals treated with tremogenic doses of harmaline, but immobilized with flaxedil, have been compared with those of non-treated controls. An increased radioactivity in specific regions of the olivo-cerebellar system including parts of the medial and dorsal accessory olive and the corresponding receiving molecular layer have been found. No involvement of the granule cell layer nor of the nuclear cells has been observed. It is therefore suggested that the tremogenic rhythmicity of the cerebellar output is organized uniquely by an increased climbing fiber input.