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Updated: Jun 23, 2026
09:16
A General Method for Evaluating Deep Brain Stimulation Effects on Intravenous Methamphetamine Self-Administration
Published on: January 22, 2016
Diadenosine tetraphosphate reduces toxicity caused by high-dose methamphetamine administration.
Brandon K Harvey1, Jenny Chou, Hui Shen
1National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD 21224, United States.
Neurotoxicology
|May 16, 2009
Summary
Diadenosine tetraphosphate (AP4A) protects brain cells from methamphetamine toxicity. This study demonstrates AP4A
Area of Science:
- Neuroscience
- Pharmacology
Background:
- Diadenosine tetraphosphate (AP4A) is an endogenous purinergic ligand in the brain.
- Previous research indicates AP4A reduces 6-hydroxydopamine-induced neurodegeneration.
Purpose of the Study:
- To investigate the protective effects of AP4A against methamphetamine (MA)-induced neurotoxicity.
Main Methods:
- Primary neuronal cultures from rat ventral mesencephalic tissue were used for in vitro studies.
- Adult rats received intracerebroventricular AP4A followed by MA injections for in vivo studies.
- Tyrosine hydroxylase (TH) immunoreactivity, cleaved caspase-3, TUNEL labeling, and locomotor activity were assessed.
Main Results:
- MA treatment decreased TH immunoreactivity and increased apoptosis markers (cleaved caspase-3, TUNEL) in vitro.
- AP4A pretreatment attenuated MA-induced neurotoxicity and apoptosis in vitro.
- In vivo, AP4A antagonized MA-induced reduction in locomotor activity and TH fiber density, while reducing apoptosis markers.
Conclusions:
- AP4A exhibits significant neuroprotective effects against methamphetamine toxicity in both in vitro and in vivo models.
- The mechanism of AP4A's protection involves the suppression of MA-induced apoptosis.
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