Role of the Striatal Cholinergic System in the Pathophysiology of Dystonia

Overview

Dystonia is defined as a syndrome of sustained muscle contractions resulting in repetitive movements and abnormal postures. DYT1 is the most common form of genetic dystonia, but the link between genomic mutations and phenotypic expression remains largely unknown. Furthermore, secondary forms of dystonia have highlighted the role of the basal ganglia, particularly the putamen in the pathophysiology of the disease. Experimental results in a genetic model of dystonia in rodents suggest that cholinergic inter-neurons (ACh-I) of the putamen play a critical role in the pathological process of plasticity in the cortico-striatal synapse. However, these results have not been demonstrated in humans.

The purpose of this study is to demonstrate that the phenotype of dystonia is associated with the degree of striatal ACh-I alterations. In this molecular imaging study, the investigators will directly test this hypothesis using a PET radiotracer of the vesicular acetylcholine transporter (VAT). Their goal is to explore the relationships between cholinergic dysfunction and clinical disease expression and the associated morphological and functional alterations. The experimental protocol will also include multimodal MRI, MRI diffusion tensor (to study the microscopic structure of white matter) and functional MRI of the resting state (to study the functional organization of cerebral cholinergic networks at rest).

Conditions