Chronic intermittent L-DOPA treatment induces changes in dopamine release
Författare
Summary, in English
3,4-Dihydroxyphenyl-l-alanine (l-DOPA)-induced dyskinesia often develops as a side effect of chronic l-DOPA therapy. This study was undertaken to investigate dopamine (DA) release upon l-DOPA treatment. Chronoamperometric measurements were performed in unilaterally DA-depleted rats, chronically treated with l-DOPA, resulting in dyskinetic and non-dyskinetic animals. Normal and lesioned l-DOPA naive animals were used as controls. Potassium-evoked DA releases were significantly reduced in intact sides of animals undertaken chronic l-DOPA treatment, independent on dyskinetic behavior. Acute l-DOPA further attenuated the amplitude of the DA release in the control sides. In DA-depleted striata, no difference was found in potassium-evoked DA releases, and acute l-DOPA did not affect the amplitude. While immunoreactivity to serotonin uptake transporter was higher in lesioned striata of animals displaying dyskinetic behavior, no correlation could be documented between serotonin transporter-positive nerve fiber density and the amplitude of released DA. In conclusions, the amplitude of potassium-evoked DA release is attenuated in intact striatum after chronic intermittent l-DOPA treatment. No change in amplitude was found in DA-denervated sides of either dyskinetic or non-dyskinetic animals, while release kinetics were changed. This indicates the importance of studying DA release dynamics for the understanding of both beneficial and adverse effects of l-DOPA replacement therapy.
Avdelning/ar
Publiceringsår
2009
Språk
Engelska
Sidor
998-1008
Publikation/Tidskrift/Serie
Journal of Neurochemistry
Volym
108
Issue
4
Länkar
Dokumenttyp
Artikel i tidskrift
Förlag
Wiley-Blackwell
Ämne
- Neurosciences
Nyckelord
- chronoamperometry
- dopamine
- serotonin transporter
- 5-hydroxytryptamine or serotonin
- dyskinesia
- 4-dihydroxyphenyl-l-alanine induced
- 3
- 4-dihydroxyphenyl-l-alanine
Status
Published
Forskningsgrupp
- Basal Ganglia Pathophysiology
ISBN/ISSN/Övrigt
- ISSN: 1471-4159