Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2007-4-17
pubmed:abstractText
Dyskinesias represent a debilitating complication of levodopa therapy for Parkinson's disease (PD). While we recently demonstrated that levodopa-induced dyskinesia results from increased dopamine D(1) receptor-mediated transmission, we also questioned the possible role of subcellular localization of D(1) and D(2) receptors in mediating these effects as we previously showed that D(1) receptors undergo differential trafficking in striatal neurons of non-dyskinetic PD patients. Taking advantage of a monkey brain bank, we here report changes affecting the cellular and subcellular distribution of D(1) and D(2) dopamine receptors within the striatum of three experimental groups: normal, parkinsonian and dyskinetic L-dopa-treated parkinsonian animals. Our studies at both light and electron microscopy levels show a recruitment of D(1) receptor at the plasma membrane of striatal neurons in the parkinsonian animals and a strong increase of D(1) expression both at the membrane and in cytoplasm of dyskinetic animals, whereas D(2) receptor distribution is only modestly affected in all conditions. Our results rule out the hypothesis of a pathological overinternalization of dopamine receptors in levodopa-induced dyskinesia but raise the possibility for involvement of D(1) receptors in the priming phenomenon through massive and sudden internalization in response to the first ever administration of L-dopa and for an altered homologous desensitization mechanism in dyskinesia leading to an increased availability of D(1) receptors at membrane. Further experiments including parkinsonian monkeys chronically treated with L-dopa that show no dyskinesia and parkinsonian monkeys treated only once with L-dopa are now necessary to confirm our hypothesis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0969-9961
pubmed:author
pubmed:issnType
Print
pubmed:volume
26
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
452-63
pubmed:meshHeading
pubmed-meshheading:17350277-Animals, pubmed-meshheading:17350277-Antiparkinson Agents, pubmed-meshheading:17350277-Cell Compartmentation, pubmed-meshheading:17350277-Corpus Striatum, pubmed-meshheading:17350277-Cytoplasm, pubmed-meshheading:17350277-Dopamine, pubmed-meshheading:17350277-Dyskinesia, Drug-Induced, pubmed-meshheading:17350277-Female, pubmed-meshheading:17350277-Levodopa, pubmed-meshheading:17350277-Macaca fascicularis, pubmed-meshheading:17350277-Microscopy, Electron, Transmission, pubmed-meshheading:17350277-Neurons, pubmed-meshheading:17350277-Parkinsonian Disorders, pubmed-meshheading:17350277-Protein Transport, pubmed-meshheading:17350277-Receptor Aggregation, pubmed-meshheading:17350277-Receptors, Dopamine D1, pubmed-meshheading:17350277-Receptors, Dopamine D2, pubmed-meshheading:17350277-Up-Regulation
pubmed:year
2007
pubmed:articleTitle
Altered D(1) dopamine receptor trafficking in parkinsonian and dyskinetic non-human primates.
pubmed:affiliation
CNRS UMR 5227, Université Victor Segalen-Bordeaux 2, 146 rue Léo Saignat, 33076 Bordeaux, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't