Nucleocortical and intrinsic neurons of the cerebellar nuclei

The size of the nucleocortical cells in the cat follows the same frequency distribution as the central nuclear cells as a whole and as the neurons that could be retrogradely labelled from the thalamus (Fig. 109). Single neurons, intracellularly stained with HRP, with axons leaving the central nuclei in the superior cerebellar peduncle, were shown to emit collaterals, that could be traced to the cerebellar cortex (McCrea et al., 1978). Antidromic invasion and collision experiments (Tolbert et al., 1977, 1978a) also favoured a collateral origin of the nucleocortical fibers from projection neurons. 

The GABAergic-nucleocortical cells may be identical to the small nucleocortical neurons that were identified in the posterior interposed nucleus and along the boundaries of the lateral nucleus of the rat by retrograde transport of an antibody to GAD 

The existence of a rest group of neurons that remains unaffected by large lesions of the efferent cerebellar pathways in the kitten has been claimed as evidence in favour of the presence of intrinsic or nucleocortical neurons in the central nuclei (Jansen and Jansen 1955). Many of these neurons were found to be large and to be located in the posterior interposed nucleus. Intrinsic neurons of the cerebellar nuclei have been observed in Golgi preparations of the rat by Chan-Palay (1973a, 1977) as small multipolar neurons in the dentate nucleus. The terminals of these intrinsic, inhibitory neurons on the soma and dendrites of cerebellar nuclear cells were tentatively identified as small 

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