Oral administration of methylphenidate blocks the effect of cocaine on uptake at the Drosophila dopamine transporter.
Journal article, 2013

Although our understanding of the actions of cocaine in the brain has improved, an effective drug treatment for cocaine addiction has yet to be found. Methylphenidate binds the dopamine transporter and increases extracellular dopamine levels in mammalian central nervous systems similar to cocaine, but it is thought to elicit fewer addictive and reinforcing effects owing to slower pharmacokinetics for different routes of administration between the drugs. This study utilizes the fruit fly model system to quantify the effects of oral methylphenidate on dopamine uptake during direct cocaine exposure to the fly CNS. The effect of methylphenidate on the dopamine transporter has been explored by measuring the uptake of exogenously applied dopamine. The data suggest that oral consumption of methylphenidate inhibits the Drosophila dopamine transporter and the inhibition is concentration dependent. The peak height increased to 150% of control when cocaine was used to block the dopamine transporter for untreated flies but only to 110% for methylphenidate-treated flies. Thus, the dopamine transporter is mostly inhibited for the methylphenidate-fed flies before the addition of cocaine. The same is true for the rate of the clearance of dopamine measured by amperometry. For untreated flies the rate of clearance changes 40% when the dopamine transporter is inhibited with cocaine, and for treated flies the rate changes only 10%. The results were correlated to the in vivo concentration of methylphenidate determined by CE-MS. Our data suggest that oral consumption of methylphenidate inhibits the Drosophila dopamine transporter for cocaine uptake, and the inhibition is concentration dependent.

Animals

Drosophila melanogaster

Cocaine

metabolism

Drug

Administration

antagonists & inhibitors

Animals

Dopamine Plasma Membrane Transport Proteins

antagonists & inhibitors

Methylphenidate

Dose-Response Relationship

metabolism

administration & dosage

Oral

Genetically Modified

Male

Author

E. C. Berglund

University of Gothenburg

Monique A Makos

Pennsylvania State University

Jacqueline Keighron

Chalmers, Chemical and Biological Engineering, Analytical Chemistry

Nhu TN Phan

University of Gothenburg

M. L. Heien

University of Arizona

Andrew Ewing

University of Gothenburg

ACS Chemical Neuroscience

1948-7193 (ISSN)

Vol. 4 4 566-74

Subject Categories

Chemical Sciences

DOI

10.1021/cn3002009

PubMed

23402315

More information

Latest update

4/6/2018 1