A study of chemical neuroanatomy on the neurotensinergic system in the human cerebellar cortex

Authors:
Paolo Flace (1,2), Diana Galletta (3), Demetrio Milardi (4), Vincenzo Coviello (2), Giulio Fata (2), Rosanna Mallamaci (5), Andrea Marzullo (6), Antonella Bizzoca (7), Gianfranco Gennarini (7), Angelo Quartarone (8)

Organisations:
1: Medical School University of Bari 'Aldo Moro', Italy
Hospital Structures of Universo Salute Opera Don Uva, Bisceglie, Italy
2: Hospital Structures of Universo Salute Opera Don Uva, Bisceglie, Italy
3: Unit of Psychiatry and Psychology, Federico II University Hospital, Naples, Italy
4: Department of Biomedical, Dental Sciences and Morphological and Functional Images, University of Messina, Messina, Italy
5: Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari ‘Aldo Moro’, Bari, Italy
6: Section of Molecular Pathology, Department of Precision and Regenerative Medicine and Ionian Area (DiMePRe-J), University of Bari ‘Aldo Moro’, Bari, Italy
7: Department of Translational Biomedicine and Neuroscience “DiBraiN”, University of Bari ‘Aldo Moro’, Bari, Italy
8: IRCCS Centro Neurolesi ‘Bonino Pulejo’, Messina, Italy

Presenting author:
Paolo Flace

Exposition date:
Friday, September 15, 2023

Exposition position:
121/1

Neurotensin (NT) is a neuropeptide largely distributed in the mammals nervous systems. NT together dopamine (DA) play a considerable role in neuromodulation mechanisms. Studies indicate a role of NT in DA-related disorders. In the cerebellum no data are available on the presence of intrinsic neurotensinergic neurons, and only the neurotensin receptor subtypes NTR2 and NTR3 has been detected. Therefore, the aim of this study, was to evaluate in the human cerebellar cortex, the presence of an intrinsic neuronal neurotensinergic system. The study was carried out on fragments of postmortem human cerebellar cortex 36-48h after death. Each fragment were fixed in an picric acid and aldehyde solution, embedded in paraffin, cut into 5 μm sections, and subjected to light microscopy immunohistochemical procedures using rabbit and goat polyclonal antibodies respectively against NT and NTR1. For positive controls fragments of rat intestine subjected to the same experimental procedure were used. In the human cerebellar cortex, NT and NTR1 immunoreactivity were observed in the molecular layer, in subpopulations of stellate and basket neurons; in the Purkinje neuron layer, in a subpopulation of Purkinje neurons; in the granular layer, in a subpopulation of granules and Golgi neurons and in some non-traditional large neurons (i.e. candelabrum, synarmotic, perivascular neurons). NTR1 immunoreactivity was also observed in form of fine ‘puncta’ (putative axon terminals) in the neuropil and in close relationship to the wall of microvessels. This study demonstrate in the human cerebellar cortex the presence of a neurotensinergic neuronal system, may involved in neuromodulation of associative and projective circuits, in microvascular innervation. Moreover, we plan to carry out further studies to evaluate the co-expression level of the corticocerebellar neurotensiergic system with the cerebellar dopaminergic system and its possible role in DA-related disorders such as Parkinson’s disease and schizophrenia.