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- Picconi, B, et al.
(författare)
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Abnormal Ca2+-calmodulin-dependent protein kinase II function mediates synaptic and motor deficits in experimental parkinsonism
- 2004
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Ingår i: The Journal of Neuroscience. - 1529-2401. ; 24:23, s. 5283-5291
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Tidskriftsartikel (refereegranskat)abstract
- The NMDA receptor complex represents a key molecular element in the pathogenesis of long-term synaptic changes and motor abnormalities in Parkinson's disease (PD). Here we show that NMDA receptor 1 (NR1) subunit and postsynaptic density (PSD)-95 protein levels are selectively reduced in the PSD of dopamine (DA)-denervated striata. These effects are accompanied by an increase in striatal levels of alphaCa(2+)-calmodulin-dependent protein kinase II (alphaCaMKII) autophosphorylation, along with a higher recruitment of activated alphaCaMKII to the regulatory NMDA receptor NR2A-NR2B subunits. Acute treatment of striatal slices with R(+)-7-chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzaz epine hydrochloride, but not with L-sulpiride, mimicked the effect of DA denervation on both alphaCaMKII autophosphorylation and corticostriatal synaptic plasticity. In addition to normalizing alphaCaMKII autophosphorylation levels as well as assembly and anchoring of the kinase to the NMDA receptor complex, intrastriatal administration of the CaMKII inhibitors KN-93 (N-[2-[[[3-(4-chlorophenyl)-2-propenyl] methylamino] methyl] phenyl]-N-(2-hydroxyethyl)-4-methoxybenzenesulfonamide) and antennapedia autocamtide-related inhibitory peptide II is able to reverse both the alterations in corticostriatal synaptic plasticity and the deficits in spontaneous motor behavior that are found in an animal model of PD. The same beneficial effects are produced by a regimen of L-3,4-dihydroxyphenylalanine(L-DOPA) treatment, which is able to normalize alphaCaMKII autophosphorylation. These data indicate that abnormal alphaCaMKII autophosphorylation plays a causal role in the alterations of striatal plasticity and motor behavior that follow DA denervation. Normalization of CaMKII activity may be an important underlying mechanism of the therapeutic action of L-DOPA in PD.
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| 2. |
- Stefanova, N, et al.
(författare)
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Effects of pulsatile L-DOPA treatment in the double lesion rat model of striatonigral degeneration (multiple system atrophy)
- 2004
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Ingår i: Neurobiology of Disease. - : Elsevier BV. - 0969-9961. ; 15:3, s. 630-639
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Tidskriftsartikel (refereegranskat)abstract
- We examined the role of a striatal lesion in the development of L-DOPA-induced abnormal involuntary movements (AlMs) using the double lesion rat model of striatonigral degeneration (SND), the underlying neuropathological substrate of parkinsonism associated with multiple system atrophy (MSA-P), in comparison to a Parkinson's disease (PD) rat model. L-DOPA administration reliably induced AlMs in SND and PD rats in a dose-dependent fashion. AlMs occurred significantly earlier in SND compared to PD rats. There was a mild, but significant, transient increase of orolingual AlMs during the first week of low-dose L-DOPA treatment in SND. Whereas L-DOPA significantly improved contralateral forelimb akinesia in PD rats, there was no beneficial effect in SND rats. Striatal FosB/DeltaFosB up-regulation in SND and PD rats correlated with the severity of L-DOPA-induced dyskinesias. Pulsatile L-DOPA administration in the double lesion SND rat model replicates salient features of the human disease MSA-P, including loss of the anti-akinetic L-DOPA response and induction of dyskinesias with transient orolingual predominance. (C) 2004 Elsevier Inc. All rights reserved.
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