Abstract |
To assess the role of dopamine receptors in the genesis of dyskinesia, we have used quantitative autoradiography to determine the effect of chronic L-dopa administration on dopamine D-1 (using [3H] SCH 23390), D-2 (using [3H] spiperone) and D-3 (using [3H]7- OH-DPAT) receptor binding levels in the striatum of dyskinetic or non-dyskinetic monkeys. Total and subregional striatal analysis showed no difference in D-1, D-2 or D-3 receptor binding in the caudate and putamen between monkeys receiving high dose L-dopa treatment with marked dyskinesia and those without dyskinesia compared to untreated animals. It thus appears unlikely that changes in dopamine receptor expression are a primary cause of L-dopa induced dyskinesia. Rather, a functional dissociation of D-2 receptor coupling to co-expressed enkephalin/ adenosine-2a receptor activity in the striato-GPe indirect pathway may be more important in the development or expression of L-dopa-induced involuntary movements.
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Authors | B Y Zeng, R K Pearce, G M MacKenzie, P Jenner |
Journal | Journal of neural transmission (Vienna, Austria : 1996)
(J Neural Transm (Vienna))
Vol. 108
Issue 8-9
Pg. 925-41
( 2001)
ISSN: 0300-9564 [Print] Austria |
PMID | 11716146
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Benzazepines
- Dopamine Agents
- Dopamine Antagonists
- Receptor, Adenosine A2A
- Receptors, Dopamine
- Receptors, Purinergic P1
- Levodopa
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Topics |
- Animals
- Benzazepines
(pharmacology)
- Dopamine Agents
(pharmacology)
- Dopamine Antagonists
(pharmacology)
- Dose-Response Relationship, Drug
- Drug Administration Schedule
- Dyskinesia, Drug-Induced
(metabolism, physiopathology)
- Female
- Levodopa
(pharmacology)
- Macaca fascicularis
- Male
- Neostriatum
(drug effects, metabolism, physiopathology)
- Neurons
(drug effects, metabolism)
- Radioligand Assay
- Receptor, Adenosine A2A
- Receptors, Dopamine
(drug effects, metabolism)
- Receptors, Purinergic P1
(drug effects, metabolism)
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