Parkinson's disease (PD) is associated with emotional abnormalities. Dopaminergic medications ameliorate Parkinsonian motor symptoms, but less is known regarding the impact of dopaminergic agents on affective processing, particularly in depressed PD (dPD) patients. The aim of this study was to examine the effects of dopaminergic pharmacotherapy on brain activation to emotional stimuli in depres...

Depression is common in Parkinson's disease and is associated with cognitive impairment. Dopaminergic medications are effective in treating the motor symptoms of Parkinson's disease; however, little is known regarding the effects of dopaminergic pharmacotherapy on cognitive function in depressed Parkinson patients. This study examines the neuropsychological effects of dopaminergic pharmacothera...

Parkinson’s disease (PD), which is characterized by the degeneration of dopaminergic neurons in the substantia nigra pars compacta, is accompanied by symptoms of muscular rigidity, bradykinesia, rest tremor, and loss of postural balance (Fearnley & Lees, 1991). Mitochondrial dysfunction by reactive oxygen species (ROS)-induced oxidative stress has also been suggested to be important in the loss...

OBJECTIVE To determine the role of damage to neuronal systems, especially the dopaminergic system, in patients with symptomatic dystonia and mesencephalic lesions. DESIGN Stereotaxic magnetic resonance imaging analysis and positron emission tomography after the administration of fluorodopa F 18. PATIENTS Of a group of 48 patients with unilateral dystonia following a stroke, 7 patients with ...

Dopaminergic neurons represent less than 1% of the total number of neurons in the brain. This low amount of neurons regulates important brain functions such as motor control, motivation, and working memory. Nigrostriatal dopaminergic neurons selectively degenerate in Parkinson's disease (PD). This progressive neuronal loss is unequivocally associated with the motors symptoms of the pathology (b...

OBJECTIVE Loss of function mutations in PINK1 typically lead to early onset Parkinson disease (PD). Zebrafish (Danio rerio) are emerging as a powerful new vertebrate model to study neurodegenerative diseases. We used a pink1 mutant (pink(-/-) ) zebrafish line with a premature stop mutation (Y431*) in the PINK1 kinase domain to identify molecular mechanisms leading to mitochondrial dysfunction a...

Converging evidence implicates the dopaminergic system and the prefrontal and nigrostriatal regions in the pathophysiology of attention deficit hyperactivity disorder (ADHD). Using positron emission tomography (PET) with [fluorine-18]fluorodopa (F18-DOPA), we compared the integrity of the presynaptic dopaminergic function between 17 ADHD adults and 23 healthy controls. The ratio of the isotope ...

To identify small molecules that induce dopaminergic neurons from neural stem cells (NSCs) is promising for therapy of Parkinson's disease. Here we report the results of analyzing structurally related steroids in traditional Chinese medicine to identify agents that enhance dopaminergic differentiation of NSCs. Using P19 cells transfected by tyrosine hydroxylase (TH) promoter reporter construct,...

Rotenone is a widely used pesticide and a potent inhibitor of mitochondrial complex I (NADH-quinone reductase) that elicits the degeneration of dopaminergic neurons and thereby the appearance of a parkinsonian syndrome. Here we have addressed the alterations induced by rotenone at the functional, morphological and molecular levels in the retina, including those involving both dopaminergic and n...

Epidemiological evidence suggests that caffeine or its metabolites reduce the risk of developing Parkinson's disease, possibly by protecting dopaminergic neurons, but the underlying mechanism is not clearly understood. Here, we show that the primary metabolite of caffeine, paraxanthine (PX; 1, 7-dimethylxanthine), was strongly protective against neurodegeneration and loss of synaptic function i...