Purkinje cells motilin

Certain inconsistencies in the results on the localization of GABA in Purkinje cells were discussed by Chan-Palay (1984). She concluded that GABA is present in varying amounts in different Purkinje cells and that it may co-exist with other neuroactive substances, notably with motilin and taurine, that also produce an inhibitory action on postsynaptic cells (Fig. 16). The presence of motilin in Purkinje cells was demonstrated with an antibody directed against conjugates of motilin (Chan-Palay et al., 1981 Nilaver et al., 1982). More than half of the Purkinje cells of the rat are immunoreaetive for this antibody and in human cerebellum their proportion was even higher (Nilaver et al.,... 

Chan-Palay et al. (1981) found eoexistence of GAD and motilin in 10-20% of the Purkinje cells of the rat. The presenee of motilin in Purkinje cells has, however, been disputed by Lange (1986), who was unable to demonstrate the presence of motilin using radioimmuno-assay and reversed phase HPLC in extracts of rat cerebellum. Only one of Lange s anti-motilin antibodies, all of which had been demonstrated to be effective in demonstrating motilin-like immunoreactivity in rat duodenum, was found to im-munoreaet with Purkinje cells in immunocytochemical studies with rat cerebellum. 

Chan-Palay s description of the zonal distribution of motilin and CSADC-im-munoreactive Purkinje cells does not offer clues for a comparison with similar longitu-... 

Fig. 129. Schematic drawing of the distribution of motilin-immunoreactive (M-i) Purkinje cells (open triangles) and glutamic acid decarboxylase-immunoreactive (GAD-i) Purkinje cells (filled circles) in a coronal section of rat cerebellum. M-i cells and GAD-i cells are both more concentrated in the flocculus and the paraflocculus than elsewhere. Both cell types occur in the vermis and participate in the formation of the sagittal microzones (arrows). M-i terminal axon projections in the deep cerebellar nuclei are heaviest in the dentate (D left side) and GAD-i projections are heaviest in the lateral vestibular nucleus (LV right side). 1 = interposed nucleus F = fastigial nucleus. Chan-Palay et al. (1981).

Chan-Palay V, Nilaver G, Palay SL, Beinfeld MC, Zimmerman EA, Wu JY, O Donohue TL (1981) Chemical heterogeneity in cerebellar Purkinje cells Existence and coexistence of glutamic acid decarboxylase-like and motilin-like immunoreactivities. Proc. Nall. Acad. Sci. USA, 78, 7787-7791. 

Nilaver G, Defendini R, Zimmerman EA, Beinfeld MC, O Donohue TL (1982) Motilin in the Purkinje cell of the cerebellum. Nature, 295, 597-598. 

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