Fuming over Parkinson disease

Abstract

One of the challenges in developing a strategy for modifying the inexorable progression of neurodegenerative disorders like Parkinson disease (PD) is to develop practical methods to detect pathologic changes prior to the onset of symptoms in appropriate individuals. Functional neuroimaging with PET may be helpful in this regard. Tracers such as 6-[18F]fluoro-l-dopa (FDOPA) or [11C]dihydrotetrabenazine bind to presynaptic dopaminergic nerve endings. Studies in PD with these compounds consistently demonstrate a characteristic rostrocaudal gradient of decreased striatal tracer uptake corresponding to the pattern of presynaptic dopaminergic nerve terminal dysfunction. This technique has been extended successfully to studies of asymptomatic individuals who are thought to be at risk for the development of PD. Subclinical dysfunction in the nigrostriatal dopamine system has been demonstrated in asymptomatic subjects exposed to MPTP1 and in subjects with a high genetic risk of PD.2 While the underlying etiology of the majority of cases of PD is unknown, there is evidence that exposure to manganese, even at relatively low levels, can result in a spectrum of neurologic …