Étude neuronale unitaire des projections dopaminergiques chez le singe

 

Dymka Coudé

Institut universitaire en santé mentale de Québec (IUSMQ)

 

Domaine : Neurosciences, santé mentale et toxicomanies

Programme : Formation de maîtrise

Concours 2016-2017

Partenaire:

Parkinson Québec

Parkinson's disease is a chronic neurological disease that affects over 100,000 persons in Canada. Motor symptoms of the disease occur following the progressive degeneration of dopaminergic neurons located in the substantia nigra pars compacta. For reasons that are still unknown, the dopamine neurons of the ventral tegmental area, a region adjacent to the substantia nigra, are spared in parkinsonian patients. To unravel the mystery underlying the selective death of dopamine neurons of the substantia nigra in Parkinson's disease, we have undertaken a research project to shed a new light on the morphological organization of the substantia nigra neurons and to compare this organization with neurons of the ventral tegmental area.

The main hypothesis of my research project states that the neurons of the substantia nigra are endowed with a complex axonal arborisation compared to those of the VTA. For the very first time in primates, the entire axonal arborization of dopamine neurons will be traced and entirely reconstructed in three-dimensions. This will provide a clear picture of the complex morphological organization of these neurons and will help to establish a link towards the selective vulnerability of these neurons to neurodegenerative processes at play in Parkinson's disease. The neurochemical content of these neurons will also be investigated. We will look for the presence of calbindin, a calcium binding protein that might play a significant neuroprotective role. We believe that dopamine neurons that harbours a complex morphological organization and do not contain calbindin are more prone to neurodegeneration in Parkinson's disease.