Cerebellar nuclei cells

IHC shows CYP2B6 in neurons and astrocytes, higher in smokers and alcoholics especially in cerebellar Purkinje cells and hippocampal pyramidal neurons, also caudate nucleus and putamen (Miksys et al., 2003). 

The (central) cerebellar nuclei and the lateral vestibular nucleus of Deiters receive the axons of the Purkinje cells of the cerebellar cortex and serve as the main output stations of the cerebellum. The vermis and the flocculus also project to other vestibular nuclei, but here the Purkinje cell axons compete with vestibular root fibers, intrinsic and commissural vestibular connections and projections from the medial cerebellar nucleus and, therefore, are not the dominant afferent system. 

Fig. 104. Two transverse, AChE-incubated sections through the cerebellar nuclei of the cat, A. Rostral section. B. Caudal section. Note medium-sized cells of dorsal group y in floccular peduncle and strongly AChE positive ventral group y along dorsal border of restiform body in (A) U-shaped nucleus between IP and F in (B). cr = restiform body F = fastigial nucleus flo-i-y = floccular peduncle with group y lA = anterior interposed nucleus IP = posterior interposed nucleus IP/F = U-shaped nucleus between F and IP L = lateral cerebellar nucleus sad = stria acoustica dorsalis.

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... 

Fig. 144. Localization of retrogradely labelled Purkinje cells (open circles) from an injection of WGA-HRP in the dorsolateral protuberance of the medial cerebellar nucleus (left) and of anterograde transport of Phaseolus vulgaris leucaglutinin (PhaL) in climbing fibers (stripes) from the medial portion of the MAO (tectorecipient area), with respect to bands of Zebrin-I labelled Purkinje cells in the rat. Reconstructions from sections double-stained for Zebrin and WGA-HRP or PhaL. Numbering of Zebrin-immuno-reactive Purkinje cell zones according to Hawkes and Leclerc (1987). COP = copula pyramidis Crl(II) = crus I(II) of the ansiform lobule PMD =paramedian lobule SI = simple lobule I-X = lobules I-X. Voogd et al. (1991b).

Fig. 146. Parasagittal section of the rat cerebellar vermis immunostained with antiserum to calretinin. Folia are labelled with roman numerals according to Larsell. The pattern of immunoreactivity in the nodulus (lobule X) and portion of the ventral uvula (lobule IXd) differs from that in the other vermal folia. While in most of the vermis weak immunoreactivity is present in granule cell bodies within the granular layer and in parallel fibers within the molecular layer, in the folia X and IXd of the vestibulo-cerebellum the immunoreaction product is largely localized in unipolar brush cells and mossy fibers, MN, medial cerebellar nucleus. Bar = 1 mm. Floris et al. (1994).

Fig. 164. The nucleo-olivary projection in the rat. Data from Ruigrok and Voogd (1990). Upper and lower block diagrams represent the cerebellar and vestibular nuclei, and the subdivisions of the inferior olive respectively. According to Ruigrok and Voogd (1990) the cerebellar nuclei and their olivary target nuclei can be considered as a continuum, stretching from the rostral medial cerebellar nucleus, projecting to caudal MAO, to the lateral vestibular nucleus, projecting to the dorsal fold of the DAO. DL = dorsolateral protuberance of the medial cerebellar nucleus DMC = dorsomedial cell column IntA = anterior interposed nucleus IntDL = dorsolateral hump IntP = posterior interposed nucleus lOD = dorsal accessory olive lODM = dorsomedial cell column lOM = medial accessory olive lOP = principal olive Lat = lateral cerebellar nucleus LVe = lateral vestibular nucleus Med = medial cerebellar nucleus VL = ventrolateral outgrowth.

Sato Y, Kawasaki T, Ikatashi K (1982b) Zonal organization of the floccular Purkinje cells projecting to the group X of the vestibular complex and the lateral cerebellar nucleus in cats. Brain Res., 234, 430 34. 

Barbiturates act throughout the CNS nonanesthetic doses preferentially suppress polysynaptic responses. Facilitation is diminished, and inhibition usually is enhanced. The site of inhibition is either postsynaptic, as at cortical and cerebellar pyramidal cells and in the cuneate nucleus, substantia nigra, and thalamic relay neurons, or presyruq tic, as in the spinal cord. Enhancement of inhibition occurs primarily at synapses where neurotransmission is mediated by GABA acting at GABA receptors. 

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