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Updated: Jun 28, 2026
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Single Cell Measurement of Dopamine Release with Simultaneous Voltage-clamp and Amperometry
Published on: November 21, 2012
Methylphenidate-induced alterations in synaptic vesicle trafficking and activity.
Trent J Volz1, Sarah J Farnsworth, Glen R Hanson
1Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, Utah, USA.
Annals of the New York Academy of Sciences
|November 11, 2008
Summary
Methylphenidate (MPD) treatment alters dopamine transporter function and vesicle distribution in rat brains. This psychostimulant impacts dopamine (DA) sequestration and release, offering insights into neurological disorders.
Area of Science:
- Neuroscience
- Pharmacology
- Molecular Biology
Background:
- Methylphenidate (MPD) is a psychostimulant used for ADHD.
- MPD inhibits the dopamine (DA) transporter, affecting DA reuptake.
- Previous research focused on MPD's direct effects on DA transporters.
Purpose of the Study:
- To investigate the in vivo effects of MPD on vesicular monoamine transporter-2 (VMAT-2).
- To examine VMAT-2 distribution and function in different subcellular fractions.
- To understand how MPD influences DA storage and release mechanisms.
Main Methods:
- Administration of MPD to rats.
- Isolation of synaptosomal membrane and cytoplasmic vesicle fractions from rat striatum.
- Assay of VMAT-2 activity and DA content in isolated vesicle fractions.
- Measurement of K(+)-stimulated DA release from striatal suspensions.
Main Results:
- MPD administration caused VMAT-2 redistribution from synaptosomal membranes to the cytoplasm.
- MPD increased DA transport in both vesicle fractions.
- MPD elevated DA content and enhanced K(+)-stimulated DA release.
Conclusions:
- In vivo MPD treatment pharmacologically manipulates synaptic vesicle trafficking, DA sequestration, and release.
- Findings suggest MPD's complex effects on dopaminergic neurotransmission.
- These insights may aid in understanding and treating disorders of DA transmission, including ADHD, Parkinson's disease, and drug abuse.
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