Metabolic activity of the subthalamic nucleus in a primate model of L-dopa-unresponsive parkinsonism.
Increased activity of the subthalamic nucleus (STN) is critical in mediating motor symptoms of Parkinson's disease. To determine if altered STN activity also occurs in levodopa (L-Dopa)-unresponsive parkinsonism due to a combined nigral and striatal degeneration, metabolic activity of the STN was assessed using cytochrome oxidase (CO) histochemistry in monkeys with nigral, striatal, or nigral+striatal degeneration induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and/or 3-nitropropionic acid (3NP). MPTP- and MPTP+3NP-treated monkeys had a similar parkinsonian score and were clinically indistinguishable. However, CO activity in the STN was significantly increased in MPTP-induced parkinsonism but not in MPTP+3NP-induced striatonigral degeneration. These results indicate that metabolic activity of the STN is normal following a combined nigral+striatal degeneration and may help to understand the lack of effect of STN stimulation in L-Dopa-unresponsive parkinsonism.
Fernagut
Pierre-Olivier
PO
Université Victor Segalen-Bordeaux 2, Centre National de la Recherche Scientifique, Bordeaux Institute of Neuroscience, UMR 5227, Bordeaux, France.
Barraud
Quentin
Q
Bezard
Erwan
E
Ghorayeb
Imad
I
Tison
Francois
F
D000818:Animals; D003342:Corpus Striatum / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology; D004195:Disease Models, Animal; D004734:Energy Metabolism / Q000502:physiology*; D005260:Female; D007980:Levodopa / Q000008:administration & dosage*; D008252:Macaca fascicularis; D020734:Parkinsonian Disorders / Q000378:metabolism* / Q000503:physiopathology*; D013378:Substantia Nigra / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology; D020531:Subthalamic Nucleus / Q000187:drug effects / Q000378:metabolism* / Q000503:physiopathology
D007980:Levodopa