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Updated: Aug 8, 2026
07:56
A Plate-Based Assay for the Measurement of Endogenous Monoamine Release in Acute Brain Slices
Published on: August 11, 2021
Methamphetamine administration reduces hippocampal vesicular monoamine transporter-2 uptake
Kristi S Rau1, Elisabeth Birdsall, Trent J Volz
1Department of Pharmacology and Toxicology, University of Utah, 30 South 2000 East, Skaggs Hall, Rm. 201, Salt Lake City, UT 84112, USA.
Summary
Methamphetamine (METH) impairs vesicular monoamine transporter-2 (VMAT-2) function in the hippocampus, primarily affecting serotonin neurons. This study links METH
Area of Science:
- Neuroscience
- Pharmacology
- Neurobiology
Background:
- Methamphetamine (METH) is known to disrupt dopamine uptake via vesicular monoamine transporter-2 (VMAT-2) in dopaminergic neurons.
- The hippocampus is significantly affected by METH, despite being innervated by serotonergic and noradrenergic neurons.
Purpose of the Study:
- To investigate if METH affects vesicular monoamine uptake in the hippocampus.
- To determine the specific neuronal pathways (serotonergic or noradrenergic) involved in METH's hippocampal effects.
Main Methods:
- Rats received repeated high-dose METH injections.
- Vesicles were purified from rat striata and hippocampi to assess monoamine uptake.
- Para-chloroamphetamine lesions were used to investigate the role of serotonergic neurons.
- Fluoxetine pretreatment was employed to examine the involvement of serotonin transporters.
Main Results:
- METH rapidly reduced hippocampal vesicular dopamine uptake within 1 hour.
- The effect on vesicular uptake was primarily linked to serotonergic nerve terminals, not noradrenergic ones.
- Fluoxetine pretreatment blocked METH's acute effect on VMAT-2 and prevented long-term serotonin depletion.
Conclusions:
- METH-induced alterations in hippocampal vesicular uptake are associated with serotonergic neurons.
- This study suggests a connection between acute METH effects on hippocampal VMAT-2 and persistent serotonergic deficits.
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