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Single Cell Measurement of Dopamine Release with Simultaneous Voltage-clamp and Amperometry
Published on: November 21, 2012
Exendin-4 decreases amphetamine-induced locomotor activity
Kevin Erreger1, Adeola R Davis, Amanda M Poe
1Department of Molecular Physiology & Biophysics, Vanderbilt University, Nashville, TN 37232, USA. kevin.erreger@vanderbilt.edu
Physiology & Behavior
|April 3, 2012
Summary
Glucagon-like peptide-1 receptor (GLP-1R) signaling, activated by exendin-4, reduces both baseline and amphetamine-induced locomotor activity in rats. This suggests GLP-1R agonists may offer a new therapeutic strategy for psychostimulant abuse.
Area of Science:
- Neuroscience
- Endocrinology
- Behavioral Pharmacology
Background:
- Glucagon-like peptide-1 (GLP-1) regulates energy metabolism and behavior via peripheral and central mechanisms.
- GLP-1 receptors (GLP-1Rs) are widespread in the central nervous system, but their role in ambulatory behavior is unclear.
- Amphetamine (AMPH) increases locomotor activity by promoting dopamine release.
Purpose of the Study:
- To investigate the role of GLP-1 receptor signaling in modulating psychostimulant-induced behaviors.
- To determine if GLP-1R agonists affect basal and amphetamine-evoked locomotor activity.
Main Methods:
- Administration of the GLP-1R agonist exendin-4 (Ex-4) to rats.
- Measurement of basal and amphetamine-induced locomotor activity.
- Assessment of anxiety- and aversion-related behaviors.
Main Results:
- Exendin-4 significantly decreased basal locomotor activity in rats.
- Exendin-4 attenuated amphetamine-induced increases in locomotor activity.
- Ex-4 did not produce anxiety or aversion-like behaviors.
Conclusions:
- GLP-1R signaling is a novel modulator of psychostimulant-induced behavioral activation.
- GLP-1R agonists represent a potential therapeutic target for psychostimulant abuse and related disorders.
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