Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2005-7-20
pubmed:abstractText
Nigrostriatal dopamine depletion disrupts striatal medium spiny neuron morphology in Parkinson's disease and modulates striatal synaptic plasticity in animal models of parkinsonism. We demonstrate that long-term nigrostriatal dopamine depletion in the rat induces evolving changes in the phosphorylation of striatal proteins critical for synaptic plasticity. Dopamine depletion increased the phosphorylation of the alpha isoform of calcium-calmodulin-dependent protein kinase II (CaMKIIalpha) at Thr286, a site associated with enhanced autonomous kinase activity, but did not alter total levels of CaMKIIalpha or other synaptic proteins. Dopamine depletion decreased CaMKIIalpha levels in postsynaptic density-enriched fractions without significant changes in other proteins. The activity of protein phosphatase 1 (PP1), a postsynaptic phosphatase that dephosphorylates CaMKII, is regulated by DARPP-32 (dopamine- and cAMP-regulated phosphoprotein of 32 kDa). Dopamine depletion had no effect on DARPP-32 phosphorylation at Thr34, but increased DARPP-32 phosphorylation at Thr75. Levodopa administration reversed the increased phosphorylation of both CaMKIIalpha and DARPP-32. Normal ageing increased the levels of PP1(gamma1 isoform) but decreased levels of the PP1gamma1-targeting proteins spinophilin and neurabin. Elevated phosphorylations of CaMKIIalpha and DARPP-32 were maintained for up to 20 months after dopamine depletion. However, phosphorylation of the CaMKII-PP1 substrate, Ser831 in the glutamate receptor GluR1 subunit, was increased only after sustained (9-20 months) dopamine depletion. Interaction of ageing-related changes in PP1 with the dopamine depletion-induced changes in CaMKIIalpha may account for enhanced GluR1 phosphorylation only after long-term dopamine depletion. These evolving changes may impact striatal synaptic plasticity, Parkinson's disease progression and the changing efficacy and side-effects associated with dopamine replacement therapy.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0953-816X
pubmed:author
pubmed:issnType
Print
pubmed:volume
22
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
247-56
pubmed:dateRevised
2009-12-31
pubmed:meshHeading
pubmed-meshheading:16029214-Aging, pubmed-meshheading:16029214-Animals, pubmed-meshheading:16029214-Calcium-Calmodulin-Dependent Protein Kinase Type 2, pubmed-meshheading:16029214-Calcium-Calmodulin-Dependent Protein Kinases, pubmed-meshheading:16029214-Corpus Striatum, pubmed-meshheading:16029214-Disease Models, Animal, pubmed-meshheading:16029214-Dopamine, pubmed-meshheading:16029214-Dopamine and cAMP-Regulated Phosphoprotein 32, pubmed-meshheading:16029214-Levodopa, pubmed-meshheading:16029214-Male, pubmed-meshheading:16029214-Nerve Tissue Proteins, pubmed-meshheading:16029214-Neural Pathways, pubmed-meshheading:16029214-Neuronal Plasticity, pubmed-meshheading:16029214-Parkinsonian Disorders, pubmed-meshheading:16029214-Phosphoprotein Phosphatases, pubmed-meshheading:16029214-Phosphoproteins, pubmed-meshheading:16029214-Phosphorylation, pubmed-meshheading:16029214-Presynaptic Terminals, pubmed-meshheading:16029214-Protein Phosphatase 1, pubmed-meshheading:16029214-Rats, pubmed-meshheading:16029214-Rats, Sprague-Dawley, pubmed-meshheading:16029214-Receptors, AMPA, pubmed-meshheading:16029214-Substantia Nigra, pubmed-meshheading:16029214-Synaptic Membranes, pubmed-meshheading:16029214-Up-Regulation
pubmed:year
2005
pubmed:articleTitle
Dopamine depletion alters phosphorylation of striatal proteins in a model of Parkinsonism.
pubmed:affiliation
Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232-0615, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural