Non-traditional large neurons in the granular layer of the cerebellar cortex. Eur J Histochem 51(Suppl 1):59-64

Dipartimento di Anatomia Umana e Istologia, Policlinico, Università di Bari, Italy.
European journal of histochemistry: EJH (Impact Factor: 2.24). 02/2007; 51 Suppl 1:59-64.
Source: PubMed

ABSTRACT The granular layer of the cerebellar cortex is composed of two groups of neurons, the granule neurons and the so-called large neurons. These latter include the neuron of Golgi and a number of other, lesser known neuron types, generically indicated as non-traditional large neurons. In the last few years, owing to the development of improved histological and histochemical techniques for studying morphological and chemical features of these neurons, some non-traditional large neurons have been morphologically well characterized, namely the neuron of Lugaro, the synarmotic neuron, the unipolar brush neuron, the candelabrum neuron and the perivascular neuron. Some types of non-traditional large neurons may be involved in the modulation of cortical intrinsic circuits, establishing connections among neurons distributed throughout the cortex, and acting as inhibitory interneurons (i.e., Lugaro and candelabrum neurons) or as excitatory ones (i.e., unipolar brush neuron). On the other hand, the synarmotic neuron could be involved in extrinsic circuits, projecting to deep cerebellar nuclei or to another cortex regions in the same or in a different folium. Finally, the perivascular neuron may intervene in the intrinsic regulation of the cortex microcirculation.

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    • "Scale Bar: A, B: 30 mm; C, D: 20 mm. synarmotic neurons, which constitute a second type of projective neuron of the cerebellar cortex (Ambrosi et al. 2007). The demonstration of CB in these neurons agrees with the assumption that CB is a calcium-binding protein prevalently expressed by neurons with a long axon, of projective type (Celio, 1990; Katsetos et al., 1993; Fortin et al., 1998; Yan and Garey, 1998). "
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    The Anatomical Record Advances in Integrative Anatomy and Evolutionary Biology 07/2014; 297(7). DOI:10.1002/ar.22921 · 1.53 Impact Factor
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    • "Deep to this, the Purkinje cell layer is a monolayer of Purkinje cell somata. Next, the granule cell layer contains primarily granule cells, Golgi cells, unipolar brush cells, and Lugaro cells (see Ambrosi et al., 2007) as well as afferent mossy fiber terminals. "
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    • "Among the " large cells " group, he identified the Golgi cells and horizontal fusiform cells quite certainly corresponding to Lugaro cells. Moreover, he noticed " non-conventional large interneurons " probably including what we now call unipolar brush cells, synarmotic neurons, candelabrum neurons and perivascular neurons (Ambrosi et al., 2007). Ramón y Cajal dedicated special attention to the cerebellar glomeruli, which he described as vacuolar dendritic cytoplasmatic islands containing granule cells dendrites, Golgi cells axonal collaterals and mossy fibres rosettes. "
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