Investigation of the Serotoninergic System in Multiple System Atrophy: a Positron Emission Tomography (PET) Study
Status:
Completed
Trial end date:
2016-03-01
Target enrollment:
Participant gender:
Summary
Multiple system atrophy (MSA) is a sporadic neurodegenerative disorder of the adult
associated to a poor prognosis. MSA is clinically characterized by the association of
extra-pyramidal, dysautonomic, cerebellar and pyramidal symptoms. Histological and biological
studies have raised the hypothesis that, beside the well known dopamine deficiency, some of
the symptoms could be related to a dysfunction in serotoninergic neurotransmission. Serotonin
is involved in the modulation of several functions impaired in MSA, such as mood, motricity
or sleep. The recent description of an association between loss of brainstem serotonin
neurons and sudden death in patients with MSA reinforced the hypothesis of a critical role
played by this neurotransmitter in the pathophysiology of this disease. Autoreceptors called
5-HT1a are strongly involved in the regulation of serotonin neurotransmission. During the
last years several radio-ligands allowing in vivo PET quantification of 5-HT1a receptors,
such as 18F-MPPF
(4-(2'-methoxyphenyl)-1-[2'-(N-2''-piridinyl)-p-fluorobenzamide]methylpiperazine), were
developed. Moreover, the investigators recently demonstrated the ability of this brain
functional imaging method to investigate, in healthy volunteers, the functional properties of
5-HT1a autoreceptors through an evaluation of their desensitization after a single oral dose
of fluoxetine.