Motor disturbances of Parkinson's disease are caused by a series of functional alterations in the basal ganglia that derive from dopamine denervation. The mechanisms underlying those functional alterations are not completely understood yet. Moreover, long-term levodopa therapy is usually associated with disabling motor complications, such as motor fluctuations and dyskinesias, whose pathophysiology also remains obscure. The long-term objective of this project is to elucidate the pathophysiologic mechanisms of abnormal motor behaviors in Parkinson's disease in view of developing new and specific therapeutic tools. Thus, this study is aimed: -firstly, to localize functional alterations in specific basal ganglia circuits; -secondly, to determine the glutamate regulation associated to an altered neuronal function; -finally, and based on the foregoing data, to explore new therapeutic approaches by interacting with the glutamatergic neurotransmission in a region-specific manner. Specifically this project comprises three aims: 1. To study the neuronal activity of individual basal ganglia regions by single cell recording in normal and various groups of parkinsonian monkeys (MPTP-treated primates) that exhibit different motor behaviors depending on treatment conditions (i.e.: parkinsonian state, its normalization, and drug-induced dyskinesias). 2. To study the glutamate receptor sensitivity in basal ganglia regions in relation to different motor conditions by comparing the binding of receptors across animal groups. 3. To study the glutamatergic blockade in restricted basal ganglia regions by determining its effects on neuronal activity and motor behavior. The research design includes techniques ranging from single- and multiple single- unit recording of neuronal activity, autoradiographic binding of receptors, to intracerebral administration of drugs in parkinsonian monkeys whose motor abnormalities closely resemble the human disease. This project proposes a novel approach to a comprehensive study of the abnormal motor function in Parkinson's disease. Thus, it will largely contribute to the rationale for new treatments that selectively target particular motor conditions. ? ?

National Institute of Health (NIH)
National Institute of Neurological Disorders and Stroke (NINDS)
Research Project (R01)
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Special Emphasis Panel (ZRG1-BDCN-2 (01))
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Oliver, Eugene J
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Emory University
Schools of Medicine
United States
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Beck, Goichi; Maehara, Shunsuke; Chang, Phat Ly et al. (2018) A Selective Phosphodiesterase 10A Inhibitor Reduces L-Dopa-Induced Dyskinesias in Parkinsonian Monkeys. Mov Disord 33:805-814
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Singh, Arun; Gutekunst, Claire A; Uthayathas, Subramaniam et al. (2015) Effects of fibroblast transplantation into the internal pallidum on levodopa-induced dyskinesias in parkinsonian non-human primates. Neurosci Bull 31:705-13
Potts, Lisa F; Park, Eun S; Woo, Jong-Min et al. (2015) Dual ?-agonist/?-antagonist opioid receptor modulation reduces levodopa-induced dyskinesia and corrects dysregulated striatal changes in the nonhuman primate model of Parkinson disease. Ann Neurol 77:930-41
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