Oral administration of methylphenidate blocks the effect of cocaine on uptake at the Drosophila dopamine transporter.

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.

Development and characterization of a voltammetric carbon-fiber microelectrode pH sensor.

This work describes the development and characterization of a modified carbon-fiber microelectrode sensor capable of measuring real-time physiological pH changes in biological microenvironments. The reagentless sensor was fabricated under ambient conditions from voltammetric reduction of the diazonium salt Fast Blue RR onto a carbon-fiber surface in aprotic media. Fast-scan cyclic voltammetry was used to probe redox activity of the p-quinone moiety of the surface-bound molecule as a function of pH.

Using In Vivo Electrochemistry to Study the Physiological Effects of Cocaine and Other Stimulants on the Drosophila melanogaster Dopamine Transporter.

Dopamine neurotransmission is thought to play a critical role in addiction reinforcing mechanisms of drugs of abuse. Electrochemical techniques have been employed extensively for monitoring in vivo dopamine changes in the brains of model organisms including rats, mice, and primates. Here, we investigated the effects of several stimulants on dopamine clearance using recently developed microanalytical tools for in vivo electrochemical measurements of dopamine in the central nervous system of Drosophila melanogaster.

Chemical measurements in Drosophila.

The fruit fly, Drosophila melanogaster, has been extensively used as a model organism in genetics research and has significantly contributed to understanding molecular, cellular and evolutionary aspects of human behavior. Recently, research has focused on developing analytical methods to obtain highly sensitive chemical quantification along with spatiotemporal information from Drosophila melanogaster. We review a number of these advances in capillary electrophoresis, high-performance liquid chromatography, mass spectrometry and technologies involving intact organisms, including in vivo electrochemistry.

In vivo electrochemical measurements of exogenously applied dopamine in Drosophila melanogaster.

Carbon-fiber microelectrodes coupled with electrochemical detection have been used extensively for the analysis of biogenic amines. In order to determine the functional role of these amines, in vivo studies have primarily used rats and mice as model organisms. Here, we report on the development of these microanalytical techniques for in vivo electrochemical detection of dopamine in the adult Drosophila melanogaster central nervous system (CNS).